Add image search demo

Update version to v1.24.0

Cargo.lock

@@ -589,7 +589,7 @@ source = "git+https://github.com/meilisearch/bbqueue#cbb87cc707b5af415ef203bdaf2
 
 [[package]]
 name = "benchmarks"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "anyhow",
  "bumpalo",
@@ -799,7 +799,7 @@ dependencies = [
 
 [[package]]
 name = "build-info"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "anyhow",
  "time",
@@ -1829,7 +1829,7 @@ dependencies = [
 
 [[package]]
 name = "dump"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "anyhow",
  "big_s",
@@ -2072,7 +2072,7 @@ checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
 
 [[package]]
 name = "file-store"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "tempfile",
  "thiserror 2.0.16",
@@ -2094,7 +2094,7 @@ dependencies = [
 
 [[package]]
 name = "filter-parser"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "insta",
  "levenshtein_automata",
@@ -2122,7 +2122,7 @@ dependencies = [
 
 [[package]]
 name = "flatten-serde-json"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "criterion",
  "serde_json",
@@ -2279,7 +2279,7 @@ dependencies = [
 
 [[package]]
 name = "fuzzers"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "arbitrary",
  "bumpalo",
@@ -2758,9 +2758,9 @@ dependencies = [
 
 [[package]]
 name = "hannoy"
-version = "0.0.9-nested-rtxns"
+version = "0.0.9-nested-rtxns-2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc5a945b92b063e677d658cfcc7cb6dec2502fe44631f017084938f14d6ce30e"
+checksum = "06eda090938d9dcd568c8c2a5de383047ed9191578ebf4a342d2975d16e621f2"
 dependencies = [
  "bytemuck",
  "byteorder",
@@ -3233,7 +3233,7 @@ dependencies = [
 
 [[package]]
 name = "index-scheduler"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "anyhow",
  "backoff",
@@ -3487,7 +3487,7 @@ dependencies = [
 
 [[package]]
 name = "json-depth-checker"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "criterion",
  "serde_json",
@@ -3996,7 +3996,7 @@ checksum = "490cc448043f947bae3cbee9c203358d62dbee0db12107a74be5c30ccfd09771"
 
 [[package]]
 name = "meili-snap"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "insta",
  "md5",
@@ -4007,7 +4007,7 @@ dependencies = [
 
 [[package]]
 name = "meilisearch"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "actix-cors",
  "actix-http",
@@ -4104,7 +4104,7 @@ dependencies = [
 
 [[package]]
 name = "meilisearch-auth"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "base64 0.22.1",
  "enum-iterator",
@@ -4123,7 +4123,7 @@ dependencies = [
 
 [[package]]
 name = "meilisearch-types"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "actix-web",
  "anyhow",
@@ -4158,7 +4158,7 @@ dependencies = [
 
 [[package]]
 name = "meilitool"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "anyhow",
  "clap",
@@ -4192,7 +4192,7 @@ dependencies = [
 
 [[package]]
 name = "milli"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "allocator-api2 0.3.1",
  "arroy",
@@ -4773,7 +4773,7 @@ checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"
 
 [[package]]
 name = "permissive-json-pointer"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "big_s",
  "serde_json",
@@ -7820,7 +7820,7 @@ dependencies = [
 
 [[package]]
 name = "xtask"
-version = "1.23.0"
+version = "1.24.0"
 dependencies = [
  "anyhow",
  "build-info",

Cargo.toml

@@ -23,7 +23,7 @@ members = [
 ]
 
 [workspace.package]
-version = "1.23.0"
+version = "1.24.0"
 authors = [
     "Quentin de Quelen <quentin@dequelen.me>",
     "Clément Renault <clement@meilisearch.com>",

Dockerfile

@@ -1,5 +1,5 @@
 # Compile
-FROM    rust:1.89-alpine3.20 AS compiler
+FROM    rust:1.89-alpine3.22 AS compiler
 
 RUN     apk add -q --no-cache build-base openssl-dev
 
@@ -20,7 +20,7 @@ RUN     set -eux; \
         cargo build --release -p meilisearch -p meilitool
 
 # Run
-FROM    alpine:3.20
+FROM    alpine:3.22
 LABEL   org.opencontainers.image.source="https://github.com/meilisearch/meilisearch"
 
 ENV     MEILI_HTTP_ADDR 0.0.0.0:7700

README.md

@@ -39,6 +39,7 @@
 ## 🖥 Examples
 
 - [**Movies**](https://where2watch.meilisearch.com/?utm_campaign=oss&utm_source=github&utm_medium=organization) — An application to help you find streaming platforms to watch movies using [hybrid search](https://www.meilisearch.com/solutions/hybrid-search?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos).
+- [**Images**](https://flickr.meilisearch.com/?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos) — Search Flickr images using [AI-powered search](https://www.meilisearch.com/solutions/hybrid-search?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos).
 - [**Ecommerce**](https://ecommerce.meilisearch.com/?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos) — Ecommerce website using disjunctive [facets](https://www.meilisearch.com/docs/learn/fine_tuning_results/faceted_search?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos), range and rating filtering, and pagination.
 - [**Songs**](https://music.meilisearch.com/?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos) — Search through 47 million of songs.
 - [**SaaS**](https://saas.meilisearch.com/?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos) — Search for contacts, deals, and companies in this [multi-tenant](https://www.meilisearch.com/docs/learn/security/multitenancy_tenant_tokens?utm_campaign=oss&utm_source=github&utm_medium=meilisearch&utm_content=demos) CRM application.

crates/index-scheduler/src/index_mapper/mod.rs

@@ -199,7 +199,7 @@ impl IndexMapper {
                 let uuid = Uuid::new_v4();
                 self.index_mapping.put(&mut wtxn, name, &uuid)?;
 
-                let index_path = self.base_path.join(uuid.to_string());
+                let index_path = self.index_path(uuid);
                 fs::create_dir_all(&index_path)?;
 
                 // Error if the UUIDv4 somehow already exists in the map, since it should be fresh.
@@ -286,7 +286,7 @@ impl IndexMapper {
         };
 
         let index_map = self.index_map.clone();
-        let index_path = self.base_path.join(uuid.to_string());
+        let index_path = self.index_path(uuid);
         let index_name = name.to_string();
         thread::Builder::new()
             .name(String::from("index_deleter"))
@@ -408,7 +408,7 @@ impl IndexMapper {
                     } else {
                         continue;
                     };
-                    let index_path = self.base_path.join(uuid.to_string());
+                    let index_path = self.index_path(uuid);
                     // take the lock to reopen the environment.
                     reopen
                         .reopen(&mut self.index_map.write().unwrap(), &index_path)
@@ -425,7 +425,7 @@ impl IndexMapper {
                     // if it's not already there.
                     match index_map.get(&uuid) {
                         Missing => {
-                            let index_path = self.base_path.join(uuid.to_string());
+                            let index_path = self.index_path(uuid);
 
                             break index_map
                                 .create(
@@ -452,6 +452,14 @@ impl IndexMapper {
         Ok(index)
     }
 
+    /// Returns the path of the index.
+    ///
+    /// The folder located at this path is containing the data.mdb,
+    /// the lock.mdb and an optional data.mdb.cpy file.
+    pub fn index_path(&self, uuid: Uuid) -> PathBuf {
+        self.base_path.join(uuid.to_string())
+    }
+
     pub fn rollback_index(
         &self,
         rtxn: &RoTxn,
@@ -492,7 +500,7 @@ impl IndexMapper {
             };
         }
 
-        let index_path = self.base_path.join(uuid.to_string());
+        let index_path = self.index_path(uuid);
         Index::rollback(milli::heed::EnvOpenOptions::new().read_txn_without_tls(), index_path, to)
             .map_err(|err| crate::Error::from_milli(err, Some(name.to_string())))
     }

crates/index-scheduler/src/processing.rs

@@ -75,6 +75,7 @@ make_enum_progress! {
     pub enum TaskCancelationProgress {
         RetrievingTasks,
         CancelingUpgrade,
+        CleaningCompactionLeftover,
         UpdatingTasks,
     }
 }

crates/index-scheduler/src/scheduler/autobatcher.rs

@@ -25,7 +25,6 @@ enum AutobatchKind {
     IndexDeletion,
     IndexUpdate,
     IndexSwap,
-    IndexCompaction,
 }
 
 impl AutobatchKind {
@@ -69,14 +68,14 @@ impl From<KindWithContent> for AutobatchKind {
             KindWithContent::IndexCreation { .. } => AutobatchKind::IndexCreation,
             KindWithContent::IndexUpdate { .. } => AutobatchKind::IndexUpdate,
             KindWithContent::IndexSwap { .. } => AutobatchKind::IndexSwap,
-            KindWithContent::IndexCompaction { .. } => AutobatchKind::IndexCompaction,
+            KindWithContent::IndexCompaction { .. }
-            KindWithContent::TaskCancelation { .. }
+            | KindWithContent::TaskCancelation { .. }
             | KindWithContent::TaskDeletion { .. }
             | KindWithContent::DumpCreation { .. }
             | KindWithContent::Export { .. }
             | KindWithContent::UpgradeDatabase { .. }
             | KindWithContent::SnapshotCreation => {
-                panic!("The autobatcher should never be called with tasks that don't apply to an index.")
+                panic!("The autobatcher should never be called with tasks with special priority or that don't apply to an index.")
             }
         }
     }
@@ -120,9 +119,6 @@ pub enum BatchKind {
     IndexSwap {
         id: TaskId,
     },
-    IndexCompaction {
-        id: TaskId,
-    },
 }
 
 impl BatchKind {
@@ -188,13 +184,6 @@ impl BatchKind {
                 )),
                 false,
             ),
-            K::IndexCompaction => (
-                Break((
-                    BatchKind::IndexCompaction { id: task_id },
-                    BatchStopReason::TaskCannotBeBatched { kind, id: task_id },
-                )),
-                false,
-            ),
             K::DocumentClear => (Continue(BatchKind::DocumentClear { ids: vec![task_id] }), false),
             K::DocumentImport { allow_index_creation, primary_key: pk }
                 if primary_key.is_none() || pk.is_none() || primary_key == pk.as_deref() =>
@@ -300,7 +289,7 @@ impl BatchKind {
 
         match (self, autobatch_kind) {
             // We don't batch any of these operations
-            (this, K::IndexCreation | K::IndexUpdate | K::IndexSwap | K::DocumentEdition | K::IndexCompaction) => {
+            (this, K::IndexCreation | K::IndexUpdate | K::IndexSwap | K::DocumentEdition) => {
                 Break((this, BatchStopReason::TaskCannotBeBatched { kind, id }))
             },
             // We must not batch tasks that don't have the same index creation rights if the index doesn't already exists.
@@ -497,7 +486,6 @@ impl BatchKind {
                 | BatchKind::IndexDeletion { .. }
                 | BatchKind::IndexUpdate { .. }
                 | BatchKind::IndexSwap { .. }
-                | BatchKind::IndexCompaction { .. }
                 | BatchKind::DocumentEdition { .. },
                 _,
             ) => {

crates/index-scheduler/src/scheduler/create_batch.rs

@@ -437,12 +437,6 @@ impl IndexScheduler {
                 current_batch.processing(Some(&mut task));
                 Ok(Some(Batch::IndexSwap { task }))
             }
-            BatchKind::IndexCompaction { id } => {
-                let mut task =
-                    self.queue.tasks.get_task(rtxn, id)?.ok_or(Error::CorruptedTaskQueue)?;
-                current_batch.processing(Some(&mut task));
-                Ok(Some(Batch::IndexCompaction { index_uid, task }))
-            }
         }
     }
 
@@ -525,17 +519,33 @@ impl IndexScheduler {
             return Ok(Some((Batch::TaskDeletions(tasks), current_batch)));
         }
 
-        // 3. we batch the export.
+        // 3. we get the next task to compact
+        let to_compact = self.queue.tasks.get_kind(rtxn, Kind::IndexCompaction)? & enqueued;
+        if let Some(task_id) = to_compact.min() {
+            let mut task =
+                self.queue.tasks.get_task(rtxn, task_id)?.ok_or(Error::CorruptedTaskQueue)?;
+            current_batch.processing(Some(&mut task));
+            current_batch.reason(BatchStopReason::TaskCannotBeBatched {
+                kind: Kind::IndexCompaction,
+                id: task_id,
+            });
+            let index_uid =
+                task.index_uid().expect("Compaction task must have an index uid").to_owned();
+            return Ok(Some((Batch::IndexCompaction { index_uid, task }, current_batch)));
+        }
+
+        // 4. we batch the export.
         let to_export = self.queue.tasks.get_kind(rtxn, Kind::Export)? & enqueued;
         if !to_export.is_empty() {
             let task_id = to_export.iter().next().expect("There must be at least one export task");
             let mut task = self.queue.tasks.get_task(rtxn, task_id)?.unwrap();
             current_batch.processing([&mut task]);
-            current_batch.reason(BatchStopReason::TaskKindCannotBeBatched { kind: Kind::Export });
+            current_batch
+                .reason(BatchStopReason::TaskCannotBeBatched { kind: Kind::Export, id: task_id });
             return Ok(Some((Batch::Export { task }, current_batch)));
         }
 
-        // 4. we batch the snapshot.
+        // 5. we batch the snapshot.
         let to_snapshot = self.queue.tasks.get_kind(rtxn, Kind::SnapshotCreation)? & enqueued;
         if !to_snapshot.is_empty() {
             let mut tasks = self.queue.tasks.get_existing_tasks(rtxn, to_snapshot)?;
@@ -545,7 +555,7 @@ impl IndexScheduler {
             return Ok(Some((Batch::SnapshotCreation(tasks), current_batch)));
         }
 
-        // 5. we batch the dumps.
+        // 6. we batch the dumps.
         let to_dump = self.queue.tasks.get_kind(rtxn, Kind::DumpCreation)? & enqueued;
         if let Some(to_dump) = to_dump.min() {
             let mut task =
@@ -558,7 +568,7 @@ impl IndexScheduler {
             return Ok(Some((Batch::Dump(task), current_batch)));
         }
 
-        // 6. We make a batch from the unprioritised tasks. Start by taking the next enqueued task.
+        // 7. We make a batch from the unprioritised tasks. Start by taking the next enqueued task.
         let task_id = if let Some(task_id) = enqueued.min() { task_id } else { return Ok(None) };
         let mut task =
             self.queue.tasks.get_task(rtxn, task_id)?.ok_or(Error::CorruptedTaskQueue)?;

crates/index-scheduler/src/scheduler/process_batch.rs

@@ -1,5 +1,6 @@
 use std::collections::{BTreeSet, HashMap, HashSet};
-use std::io::{Seek, SeekFrom};
+use std::fs::{remove_file, File};
+use std::io::{ErrorKind, Seek, SeekFrom};
 use std::panic::{catch_unwind, AssertUnwindSafe};
 use std::sync::atomic::Ordering;
 
@@ -13,7 +14,7 @@ use meilisearch_types::tasks::{Details, IndexSwap, Kind, KindWithContent, Status
 use meilisearch_types::versioning::{VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH};
 use milli::update::Settings as MilliSettings;
 use roaring::RoaringBitmap;
-use tempfile::PersistError;
+use tempfile::{PersistError, TempPath};
 use time::OffsetDateTime;
 
 use super::create_batch::Batch;
@@ -28,6 +29,9 @@ use crate::utils::{
 };
 use crate::{Error, IndexScheduler, Result, TaskId};
 
+/// The name of the copy of the data.mdb file used during compaction.
+const DATA_MDB_COPY_NAME: &str = "data.mdb.cpy";
+
 #[derive(Debug, Default)]
 pub struct ProcessBatchInfo {
     /// The write channel congestion. None when unavailable: settings update.
@@ -558,11 +562,12 @@ impl IndexScheduler {
             .set_currently_updating_index(Some((index_uid.to_string(), index.clone())));
 
         progress.update_progress(IndexCompaction::CreateTemporaryFile);
-        let pre_size = std::fs::metadata(index.path().join("data.mdb"))?.len();
+        let src_path = index.path().join("data.mdb");
-        let mut file = tempfile::Builder::new()
+        let pre_size = std::fs::metadata(&src_path)?.len();
-            .suffix("data.")
+
-            .prefix(".mdb.cpy")
+        let dst_path = TempPath::from_path(index.path().join(DATA_MDB_COPY_NAME));
-            .tempfile_in(index.path())?;
+        let file = File::create(&dst_path)?;
+        let mut file = tempfile::NamedTempFile::from_parts(file, dst_path);
 
         // 3. We copy the index data to the temporary file
         progress.update_progress(IndexCompaction::CopyAndCompactTheIndex);
@@ -574,7 +579,7 @@ impl IndexScheduler {
 
         // 4. We replace the index data file with the temporary file
         progress.update_progress(IndexCompaction::PersistTheCompactedIndex);
-        match file.persist(index.path().join("data.mdb")) {
+        match file.persist(src_path) {
             Ok(file) => file.sync_all()?,
             // TODO see if we have a _resource busy_ error and probably handle this by:
             //      1. closing the index, 2. replacing and 3. reopening it
@@ -910,9 +915,10 @@ impl IndexScheduler {
 
         let enqueued_tasks = &self.queue.tasks.get_status(rtxn, Status::Enqueued)?;
 
-        // 0. Check if any upgrade task was matched.
+        // 0. Check if any upgrade or compaction tasks were matched.
         //    If so, we cancel all the failed or enqueued upgrade tasks.
         let upgrade_tasks = &self.queue.tasks.get_kind(rtxn, Kind::UpgradeDatabase)?;
+        let compaction_tasks = &self.queue.tasks.get_kind(rtxn, Kind::IndexCompaction)?;
         let is_canceling_upgrade = !matched_tasks.is_disjoint(upgrade_tasks);
         if is_canceling_upgrade {
             let failed_tasks = self.queue.tasks.get_status(rtxn, Status::Failed)?;
@@ -977,7 +983,33 @@ impl IndexScheduler {
             }
         }
 
-        // 3. We now have a list of tasks to cancel, cancel them
+        // 3. If we are cancelling a compaction task, remove the tempfiles after incomplete compactions
+        for compaction_task in &tasks_to_cancel & compaction_tasks {
+            progress.update_progress(TaskCancelationProgress::CleaningCompactionLeftover);
+            let task = self.queue.tasks.get_task(rtxn, compaction_task)?.unwrap();
+            let Some(Details::IndexCompaction {
+                index_uid,
+                pre_compaction_size: _,
+                post_compaction_size: _,
+            }) = task.details
+            else {
+                unreachable!("wrong details for compaction task {compaction_task}")
+            };
+
+            let index_path = match self.index_mapper.index_mapping.get(rtxn, &index_uid)? {
+                Some(index_uuid) => self.index_mapper.index_path(index_uuid),
+                None => continue,
+            };
+
+            if let Err(e) = remove_file(index_path.join(DATA_MDB_COPY_NAME)) {
+                match e.kind() {
+                    ErrorKind::NotFound => (),
+                    _ => return Err(Error::IoError(e)),
+                }
+            }
+        }
+
+        // 4. We now have a list of tasks to cancel, cancel them
         let (task_progress, progress_obj) = AtomicTaskStep::new(tasks_to_cancel.len() as u32);
         progress.update_progress(progress_obj);
 

crates/index-scheduler/src/scheduler/snapshots/test_failure.rs/upgrade_failure/after_processing_everything.snap

@@ -6,7 +6,7 @@ source: crates/index-scheduler/src/scheduler/test_failure.rs
 []
 ----------------------------------------------------------------------
 ### All Tasks:
-0 {uid: 0, batch_uid: 0, status: succeeded, details: { from: (1, 12, 0), to: (1, 23, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
+0 {uid: 0, batch_uid: 0, status: succeeded, details: { from: (1, 12, 0), to: (1, 24, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
 1 {uid: 1, batch_uid: 1, status: succeeded, details: { primary_key: Some("mouse"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
 2 {uid: 2, batch_uid: 2, status: succeeded, details: { primary_key: Some("bone"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("bone") }}
 3 {uid: 3, batch_uid: 3, status: failed, error: ResponseError { code: 200, message: "Index `doggo` already exists.", error_code: "index_already_exists", error_type: "invalid_request", error_link: "https://docs.meilisearch.com/errors#index_already_exists" }, details: { primary_key: Some("bone"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("bone") }}
@@ -57,7 +57,7 @@ girafo: { number_of_documents: 0, field_distribution: {} }
 [timestamp] [4,]
 ----------------------------------------------------------------------
 ### All Batches:
-0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.23.0"}, stats: {"totalNbTasks":1,"status":{"succeeded":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
+0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.24.0"}, stats: {"totalNbTasks":1,"status":{"succeeded":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
 1 {uid: 1, details: {"primaryKey":"mouse"}, stats: {"totalNbTasks":1,"status":{"succeeded":1},"types":{"indexCreation":1},"indexUids":{"catto":1}}, stop reason: "created batch containing only task with id 1 of type `indexCreation` that cannot be batched with any other task.", }
 2 {uid: 2, details: {"primaryKey":"bone"}, stats: {"totalNbTasks":1,"status":{"succeeded":1},"types":{"indexCreation":1},"indexUids":{"doggo":1}}, stop reason: "created batch containing only task with id 2 of type `indexCreation` that cannot be batched with any other task.", }
 3 {uid: 3, details: {"primaryKey":"bone"}, stats: {"totalNbTasks":1,"status":{"failed":1},"types":{"indexCreation":1},"indexUids":{"doggo":1}}, stop reason: "created batch containing only task with id 3 of type `indexCreation` that cannot be batched with any other task.", }

crates/index-scheduler/src/scheduler/snapshots/test_failure.rs/upgrade_failure/register_automatic_upgrade_task.snap

@@ -6,7 +6,7 @@ source: crates/index-scheduler/src/scheduler/test_failure.rs
 []
 ----------------------------------------------------------------------
 ### All Tasks:
-0 {uid: 0, status: enqueued, details: { from: (1, 12, 0), to: (1, 23, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
+0 {uid: 0, status: enqueued, details: { from: (1, 12, 0), to: (1, 24, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
 ----------------------------------------------------------------------
 ### Status:
 enqueued [0,]

crates/index-scheduler/src/scheduler/snapshots/test_failure.rs/upgrade_failure/registered_a_task_while_the_upgrade_task_is_enqueued.snap

@@ -6,7 +6,7 @@ source: crates/index-scheduler/src/scheduler/test_failure.rs
 []
 ----------------------------------------------------------------------
 ### All Tasks:
-0 {uid: 0, status: enqueued, details: { from: (1, 12, 0), to: (1, 23, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
+0 {uid: 0, status: enqueued, details: { from: (1, 12, 0), to: (1, 24, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
 1 {uid: 1, status: enqueued, details: { primary_key: Some("mouse"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
 ----------------------------------------------------------------------
 ### Status:

crates/index-scheduler/src/scheduler/snapshots/test_failure.rs/upgrade_failure/upgrade_task_failed.snap

@@ -6,7 +6,7 @@ source: crates/index-scheduler/src/scheduler/test_failure.rs
 []
 ----------------------------------------------------------------------
 ### All Tasks:
-0 {uid: 0, batch_uid: 0, status: failed, error: ResponseError { code: 200, message: "Planned failure for tests.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { from: (1, 12, 0), to: (1, 23, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
+0 {uid: 0, batch_uid: 0, status: failed, error: ResponseError { code: 200, message: "Planned failure for tests.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { from: (1, 12, 0), to: (1, 24, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
 1 {uid: 1, status: enqueued, details: { primary_key: Some("mouse"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
 ----------------------------------------------------------------------
 ### Status:
@@ -37,7 +37,7 @@ catto [1,]
 [timestamp] [0,]
 ----------------------------------------------------------------------
 ### All Batches:
-0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.23.0"}, stats: {"totalNbTasks":1,"status":{"failed":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
+0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.24.0"}, stats: {"totalNbTasks":1,"status":{"failed":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
 ----------------------------------------------------------------------
 ### Batch to tasks mapping:
 0 [0,]

crates/index-scheduler/src/scheduler/snapshots/test_failure.rs/upgrade_failure/upgrade_task_failed_again.snap

@@ -6,7 +6,7 @@ source: crates/index-scheduler/src/scheduler/test_failure.rs
 []
 ----------------------------------------------------------------------
 ### All Tasks:
-0 {uid: 0, batch_uid: 0, status: failed, error: ResponseError { code: 200, message: "Planned failure for tests.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { from: (1, 12, 0), to: (1, 23, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
+0 {uid: 0, batch_uid: 0, status: failed, error: ResponseError { code: 200, message: "Planned failure for tests.", error_code: "internal", error_type: "internal", error_link: "https://docs.meilisearch.com/errors#internal" }, details: { from: (1, 12, 0), to: (1, 24, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
 1 {uid: 1, status: enqueued, details: { primary_key: Some("mouse"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
 2 {uid: 2, status: enqueued, details: { primary_key: Some("bone"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("bone") }}
 ----------------------------------------------------------------------
@@ -40,7 +40,7 @@ doggo [2,]
 [timestamp] [0,]
 ----------------------------------------------------------------------
 ### All Batches:
-0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.23.0"}, stats: {"totalNbTasks":1,"status":{"failed":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
+0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.24.0"}, stats: {"totalNbTasks":1,"status":{"failed":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
 ----------------------------------------------------------------------
 ### Batch to tasks mapping:
 0 [0,]

crates/index-scheduler/src/scheduler/snapshots/test_failure.rs/upgrade_failure/upgrade_task_succeeded.snap

@@ -6,7 +6,7 @@ source: crates/index-scheduler/src/scheduler/test_failure.rs
 []
 ----------------------------------------------------------------------
 ### All Tasks:
-0 {uid: 0, batch_uid: 0, status: succeeded, details: { from: (1, 12, 0), to: (1, 23, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
+0 {uid: 0, batch_uid: 0, status: succeeded, details: { from: (1, 12, 0), to: (1, 24, 0) }, kind: UpgradeDatabase { from: (1, 12, 0) }}
 1 {uid: 1, status: enqueued, details: { primary_key: Some("mouse"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "catto", primary_key: Some("mouse") }}
 2 {uid: 2, status: enqueued, details: { primary_key: Some("bone"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("bone") }}
 3 {uid: 3, status: enqueued, details: { primary_key: Some("bone"), old_new_uid: None, new_index_uid: None }, kind: IndexCreation { index_uid: "doggo", primary_key: Some("bone") }}
@@ -43,7 +43,7 @@ doggo [2,3,]
 [timestamp] [0,]
 ----------------------------------------------------------------------
 ### All Batches:
-0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.23.0"}, stats: {"totalNbTasks":1,"status":{"succeeded":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
+0 {uid: 0, details: {"upgradeFrom":"v1.12.0","upgradeTo":"v1.24.0"}, stats: {"totalNbTasks":1,"status":{"succeeded":1},"types":{"upgradeDatabase":1},"indexUids":{}}, stop reason: "stopped after the last task of type `upgradeDatabase` because they cannot be batched with tasks of any other type.", }
 ----------------------------------------------------------------------
 ### Batch to tasks mapping:
 0 [0,]

crates/index-scheduler/src/upgrade/mod.rs

@@ -47,6 +47,7 @@ pub fn upgrade_index_scheduler(
         (1, 21, _) => 0,
         (1, 22, _) => 0,
         (1, 23, _) => 0,
+        (1, 24, _) => 0,
         (major, minor, patch) => {
             if major > current_major
                 || (major == current_major && minor > current_minor)

crates/meilisearch/src/routes/indexes/search.rs

@@ -22,11 +22,12 @@ use crate::extractors::authentication::GuardedData;
 use crate::extractors::sequential_extractor::SeqHandler;
 use crate::metrics::MEILISEARCH_DEGRADED_SEARCH_REQUESTS;
 use crate::routes::indexes::search_analytics::{SearchAggregator, SearchGET, SearchPOST};
+use crate::routes::parse_include_metadata_header;
 use crate::search::{
     add_search_rules, perform_search, HybridQuery, MatchingStrategy, RankingScoreThreshold,
-    RetrieveVectors, SearchKind, SearchQuery, SearchResult, SemanticRatio, DEFAULT_CROP_LENGTH,
+    RetrieveVectors, SearchKind, SearchParams, SearchQuery, SearchResult, SemanticRatio,
-    DEFAULT_CROP_MARKER, DEFAULT_HIGHLIGHT_POST_TAG, DEFAULT_HIGHLIGHT_PRE_TAG,
+    DEFAULT_CROP_LENGTH, DEFAULT_CROP_MARKER, DEFAULT_HIGHLIGHT_POST_TAG,
-    DEFAULT_SEARCH_LIMIT, DEFAULT_SEARCH_OFFSET, DEFAULT_SEMANTIC_RATIO,
+    DEFAULT_HIGHLIGHT_PRE_TAG, DEFAULT_SEARCH_LIMIT, DEFAULT_SEARCH_OFFSET, DEFAULT_SEMANTIC_RATIO,
 };
 use crate::search_queue::SearchQueue;
 
@@ -345,15 +346,20 @@ pub async fn search_with_url_query(
         search_kind(&query, index_scheduler.get_ref(), index_uid.to_string(), &index)?;
     let retrieve_vector = RetrieveVectors::new(query.retrieve_vectors);
     let permit = search_queue.try_get_search_permit().await?;
+    let include_metadata = parse_include_metadata_header(&req);
+
     let search_result = tokio::task::spawn_blocking(move || {
         perform_search(
-            index_uid.to_string(),
+            SearchParams {
+                index_uid: index_uid.to_string(),
+                query,
+                search_kind,
+                retrieve_vectors: retrieve_vector,
+                features: index_scheduler.features(),
+                request_uid,
+                include_metadata,
+            },
             &index,
-            query,
-            search_kind,
-            retrieve_vector,
-            index_scheduler.features(),
-            request_uid,
         )
     })
     .await;
@@ -453,16 +459,21 @@ pub async fn search_with_post(
         search_kind(&query, index_scheduler.get_ref(), index_uid.to_string(), &index)?;
     let retrieve_vectors = RetrieveVectors::new(query.retrieve_vectors);
 
+    let include_metadata = parse_include_metadata_header(&req);
+
     let permit = search_queue.try_get_search_permit().await?;
     let search_result = tokio::task::spawn_blocking(move || {
         perform_search(
-            index_uid.to_string(),
+            SearchParams {
+                index_uid: index_uid.to_string(),
+                query,
+                search_kind,
+                retrieve_vectors,
+                features: index_scheduler.features(),
+                request_uid,
+                include_metadata,
+            },
             &index,
-            query,
-            search_kind,
-            retrieve_vectors,
-            index_scheduler.features(),
-            request_uid,
         )
     })
     .await;

crates/meilisearch/src/routes/indexes/search_analytics.rs

@@ -235,6 +235,7 @@ impl<Method: AggregateMethod> SearchAggregator<Method> {
             degraded,
             used_negative_operator,
             request_uid: _,
+            metadata: _,
         } = result;
 
         self.total_succeeded = self.total_succeeded.saturating_add(1);

crates/meilisearch/src/routes/mod.rs

@@ -45,6 +45,7 @@ use crate::routes::webhooks::{WebhookResults, WebhookSettings, WebhookWithMetada
 use crate::search::{
     FederatedSearch, FederatedSearchResult, Federation, FederationOptions, MergeFacets,
     SearchQueryWithIndex, SearchResultWithIndex, SimilarQuery, SimilarResult,
+    INCLUDE_METADATA_HEADER,
 };
 use crate::search_queue::SearchQueue;
 use crate::Opt;
@@ -184,6 +185,18 @@ pub fn is_dry_run(req: &HttpRequest, opt: &Opt) -> Result<bool, ResponseError> {
         .is_some_and(|s| s.to_lowercase() == "true"))
 }
 
+/// Parse the `Meili-Include-Metadata` header from an HTTP request.
+///
+/// Returns `true` if the header is present and set to "true" or "1" (case-insensitive).
+/// Returns `false` if the header is not present or has any other value.
+pub fn parse_include_metadata_header(req: &HttpRequest) -> bool {
+    req.headers()
+        .get(INCLUDE_METADATA_HEADER)
+        .and_then(|h| h.to_str().ok())
+        .map(|v| matches!(v.to_lowercase().as_str(), "true" | "1"))
+        .unwrap_or(false)
+}
+
 #[derive(Debug, Serialize, Deserialize, ToSchema)]
 #[serde(rename_all = "camelCase")]
 pub struct SummarizedTaskView {

crates/meilisearch/src/routes/multi_search.rs

@@ -18,10 +18,11 @@ use crate::extractors::authentication::policies::ActionPolicy;
 use crate::extractors::authentication::{AuthenticationError, GuardedData};
 use crate::extractors::sequential_extractor::SeqHandler;
 use crate::routes::indexes::search::search_kind;
+use crate::routes::parse_include_metadata_header;
 use crate::search::{
     add_search_rules, perform_federated_search, perform_search, FederatedSearch,
-    FederatedSearchResult, RetrieveVectors, SearchQueryWithIndex, SearchResultWithIndex,
+    FederatedSearchResult, RetrieveVectors, SearchParams, SearchQueryWithIndex,
-    PROXY_SEARCH_HEADER, PROXY_SEARCH_HEADER_VALUE,
+    SearchResultWithIndex, PROXY_SEARCH_HEADER, PROXY_SEARCH_HEADER_VALUE,
 };
 use crate::search_queue::SearchQueue;
 
@@ -188,6 +189,7 @@ pub async fn multi_search_with_post(
         err
     })?;
 
+    let include_metadata = parse_include_metadata_header(&req);
     let response = match federation {
         Some(federation) => {
             debug!(
@@ -209,6 +211,7 @@ pub async fn multi_search_with_post(
                 features,
                 is_proxy,
                 request_uid,
+                include_metadata,
             )
             .await;
             permit.drop().await;
@@ -279,13 +282,16 @@ pub async fn multi_search_with_post(
 
                     let search_result = tokio::task::spawn_blocking(move || {
                         perform_search(
-                            index_uid_str.clone(),
+                            SearchParams {
+                                index_uid: index_uid_str.clone(),
+                                query,
+                                search_kind,
+                                retrieve_vectors: retrieve_vector,
+                                features,
+                                request_uid,
+                                include_metadata,
+                            },
                             &index,
-                            query,
-                            search_kind,
-                            retrieve_vector,
-                            features,
-                            request_uid,
                         )
                     })
                     .await

crates/meilisearch/src/search/federated/perform.rs

@@ -22,7 +22,8 @@ use uuid::Uuid;
 use super::super::ranking_rules::{self, RankingRules};
 use super::super::{
     compute_facet_distribution_stats, prepare_search, AttributesFormat, ComputedFacets, HitMaker,
-    HitsInfo, RetrieveVectors, SearchHit, SearchKind, SearchQuery, SearchQueryWithIndex,
+    HitsInfo, RetrieveVectors, SearchHit, SearchKind, SearchMetadata, SearchQuery,
+    SearchQueryWithIndex,
 };
 use super::proxy::{proxy_search, ProxySearchError, ProxySearchParams};
 use super::types::{
@@ -41,6 +42,7 @@ pub async fn perform_federated_search(
     features: RoFeatures,
     is_proxy: bool,
     request_uid: Uuid,
+    include_metadata: bool,
 ) -> Result<FederatedSearchResult, ResponseError> {
     if is_proxy {
         features.check_network("Performing a remote federated search")?;
@@ -59,20 +61,38 @@ pub async fn perform_federated_search(
 
     let network = index_scheduler.network();
 
+    // Preconstruct metadata keeping the original queries order for later metadata building
+    let precomputed_query_metadata: Option<Vec<_>> = include_metadata.then(|| {
+        queries
+            .iter()
+            .map(|q| {
+                (
+                    q.index_uid.to_string(),
+                    q.federation_options.as_ref().and_then(|o| o.remote.clone()),
+                )
+            })
+            .collect()
+    });
+
     // this implementation partition the queries by index to guarantee an important property:
     // - all the queries to a particular index use the same read transaction.
     // This is an important property, otherwise we cannot guarantee the self-consistency of the results.
 
     // 1. partition queries by host and index
     let mut partitioned_queries = PartitionedQueries::new();
+
     for (query_index, federated_query) in queries.into_iter().enumerate() {
         partitioned_queries.partition(federated_query, query_index, &network, features)?
     }
 
     // 2. perform queries, merge and make hits index by index
     // 2.1. start remote queries
-    let remote_search =
+    let remote_search = RemoteSearch::start(
-        RemoteSearch::start(partitioned_queries.remote_queries_by_host, &federation, deadline);
+        partitioned_queries.remote_queries_by_host,
+        &federation,
+        deadline,
+        include_metadata,
+    );
 
     // 2.2. concurrently execute local queries
     let params = SearchByIndexParams {
@@ -114,11 +134,25 @@ pub async fn perform_federated_search(
     let after_waiting_remote_results = std::time::Instant::now();
 
     // 3. merge hits and metadata across indexes and hosts
-    // 3.1. merge metadata
+
+    // 3.1. Build metadata in the same order as the original queries
+    let query_metadata = precomputed_query_metadata.map(|precomputed_query_metadata| {
+        // If a remote is present, set the local remote name
+        let local_remote_name = network.local.clone().filter(|_| partitioned_queries.has_remote);
+
+        build_query_metadata(
+            precomputed_query_metadata,
+            local_remote_name,
+            &remote_results,
+            &results_by_index,
+        )
+    });
+
+    // 3.2. merge federation metadata
     let (estimated_total_hits, degraded, used_negative_operator, facets, max_remote_duration) =
         merge_metadata(&mut results_by_index, &remote_results);
 
-    // 3.2. merge hits
+    // 3.3. merge hits
     let merged_hits: Vec<_> = merge_index_global_results(results_by_index, &mut remote_results)
         .skip(federation.offset)
         .take(federation.limit)
@@ -133,7 +167,7 @@ pub async fn perform_federated_search(
         .map(|hit| hit.hit())
         .collect();
 
-    // 3.3. merge query vectors
+    // 3.4. merge query vectors
     let query_vectors = if retrieve_vectors {
         for remote_results in remote_results.iter_mut() {
             if let Some(remote_vectors) = remote_results.query_vectors.take() {
@@ -152,7 +186,7 @@ pub async fn perform_federated_search(
         None
     };
 
-    // 3.4. merge facets
+    // 3.5. merge facets
     let (facet_distribution, facet_stats, facets_by_index) =
         facet_order.merge(federation.merge_facets, remote_results, facets);
 
@@ -179,6 +213,7 @@ pub async fn perform_federated_search(
         facets_by_index,
         remote_errors: partitioned_queries.has_remote.then_some(remote_errors),
         request_uid: Some(request_uid),
+        metadata: query_metadata,
     })
 }
 
@@ -402,6 +437,7 @@ struct SearchHitByIndex {
 
 struct SearchResultByIndex {
     index: String,
+    primary_key: Option<String>,
     hits: Vec<SearchHitByIndex>,
     estimated_total_hits: usize,
     degraded: bool,
@@ -409,6 +445,61 @@ struct SearchResultByIndex {
     facets: Option<ComputedFacets>,
 }
 
+/// Builds query metadata for federated search results.
+///
+/// This function creates metadata for each query in the same order as the original queries,
+/// combining information from both local and remote search results. It handles the mapping
+/// of primary keys to their respective indexes and remotes to prevent collisions when
+/// multiple remotes have the same index_uid but different primary keys.
+fn build_query_metadata(
+    precomputed_query_metadata: Vec<(String, Option<String>)>,
+    local_remote_name: Option<String>,
+    remote_results: &[FederatedSearchResult],
+    results_by_index: &[SearchResultByIndex],
+) -> Vec<SearchMetadata> {
+    // Create a map of (remote, index_uid) -> primary_key for quick lookup
+    // This prevents collisions when multiple remotes have the same index_uid but different primary keys
+    let mut primary_key_per_index = std::collections::HashMap::new();
+
+    // Build metadata for remote results
+    for remote_result in remote_results {
+        if let Some(remote_metadata) = &remote_result.metadata {
+            for remote_meta in remote_metadata {
+                if let SearchMetadata {
+                    remote: Some(remote_name),
+                    index_uid,
+                    primary_key: Some(primary_key),
+                    ..
+                } = remote_meta
+                {
+                    let key = (Some(remote_name), index_uid);
+                    primary_key_per_index.insert(key, primary_key);
+                }
+            }
+        }
+    }
+
+    // Build metadata for local results
+    for local_meta in results_by_index {
+        if let SearchResultByIndex { index, primary_key: Some(primary_key), .. } = local_meta {
+            let key = (None, index);
+            primary_key_per_index.insert(key, primary_key);
+        }
+    }
+
+    // Build metadata in the same order as the original queries
+    let mut query_metadata = Vec::new();
+    for (index_uid, remote) in precomputed_query_metadata {
+        let primary_key =
+            primary_key_per_index.get(&(remote.as_ref(), &index_uid)).map(|pk| pk.to_string());
+        let query_uid = Uuid::now_v7();
+        // if the remote is not set, use the local remote name
+        let remote = remote.or_else(|| local_remote_name.clone());
+        query_metadata.push(SearchMetadata { query_uid, primary_key, index_uid, remote });
+    }
+    query_metadata
+}
+
 fn merge_metadata(
     results_by_index: &mut Vec<SearchResultByIndex>,
     remote_results: &Vec<FederatedSearchResult>,
@@ -420,6 +511,7 @@ fn merge_metadata(
     let mut max_remote_duration = Duration::ZERO;
     for SearchResultByIndex {
         index,
+        primary_key: _,
         hits: _,
         estimated_total_hits: estimated_total_hits_by_index,
         facets: facets_by_index,
@@ -448,6 +540,7 @@ fn merge_metadata(
         degraded: degraded_for_host,
         used_negative_operator: host_used_negative_operator,
         remote_errors: _,
+        metadata: _,
         request_uid: _,
     } in remote_results
     {
@@ -576,7 +669,12 @@ struct RemoteSearch {
 }
 
 impl RemoteSearch {
-    fn start(queries: RemoteQueriesByHost, federation: &Federation, deadline: Instant) -> Self {
+    fn start(
+        queries: RemoteQueriesByHost,
+        federation: &Federation,
+        deadline: Instant,
+        include_metadata: bool,
+    ) -> Self {
         let mut in_flight_remote_queries = BTreeMap::new();
         let client = reqwest::ClientBuilder::new()
             .connect_timeout(std::time::Duration::from_millis(200))
@@ -596,7 +694,10 @@ impl RemoteSearch {
                     // never merge distant facets
                     proxy_federation.merge_facets = None;
                     let params = params.clone();
-                    async move { proxy_search(&node, queries, proxy_federation, &params).await }
+                    async move {
+                        proxy_search(&node, queries, proxy_federation, &params, include_metadata)
+                            .await
+                    }
                 }),
             );
         }
@@ -640,6 +741,13 @@ impl RemoteSearch {
                             continue 'remote_queries;
                         }
 
+                        // Add remote name to metadata
+                        if let Some(metadata) = res.metadata.as_mut() {
+                            for meta in metadata {
+                                meta.remote = Some(node_name.clone());
+                            }
+                        }
+
                         federation.insert(
                             FEDERATION_REMOTE.to_string(),
                             serde_json::Value::String(node_name.clone()),
@@ -735,6 +843,7 @@ impl SearchByIndex {
             }
         };
         let rtxn = index.read_txn()?;
+        let primary_key = index.primary_key(&rtxn)?.map(|pk| pk.to_string());
         let criteria = index.criteria(&rtxn)?;
         let dictionary = index.dictionary(&rtxn)?;
         let dictionary: Option<Vec<_>> =
@@ -761,6 +870,12 @@ impl SearchByIndex {
             return Err(error);
         }
         let mut results_by_query = Vec::with_capacity(queries.len());
+
+        // all queries for an index share the same budget
+        let time_budget = match cutoff {
+            Some(cutoff) => TimeBudget::new(Duration::from_millis(cutoff)),
+            None => TimeBudget::default(),
+        };
         for QueryByIndex { query, weight, query_index } in queries {
             // use an immediately invoked lambda to capture the result without returning from the function
 
@@ -830,17 +945,13 @@ impl SearchByIndex {
 
                 let retrieve_vectors = RetrieveVectors::new(query.retrieve_vectors);
 
-                let time_budget = match cutoff {
-                    Some(cutoff) => TimeBudget::new(Duration::from_millis(cutoff)),
-                    None => TimeBudget::default(),
-                };
-
                 let (mut search, _is_finite_pagination, _max_total_hits, _offset) = prepare_search(
                     &index,
                     &rtxn,
                     &query,
                     &search_kind,
-                    time_budget,
+                    // clones of `TimeBudget` share the budget rather than restart it
+                    time_budget.clone(),
                     params.features,
                 )?;
 
@@ -987,6 +1098,7 @@ impl SearchByIndex {
             })?;
         self.results_by_index.push(SearchResultByIndex {
             index: index_uid,
+            primary_key,
             hits: merged_result,
             estimated_total_hits,
             degraded,

crates/meilisearch/src/search/federated/proxy.rs

@@ -7,7 +7,7 @@ use serde::de::DeserializeOwned;
 use serde_json::Value;
 
 use super::types::{FederatedSearch, FederatedSearchResult, Federation};
-use crate::search::SearchQueryWithIndex;
+use crate::search::{SearchQueryWithIndex, INCLUDE_METADATA_HEADER};
 
 pub const PROXY_SEARCH_HEADER: &str = "Meili-Proxy-Search";
 pub const PROXY_SEARCH_HEADER_VALUE: &str = "true";
@@ -98,6 +98,7 @@ pub async fn proxy_search(
     queries: Vec<SearchQueryWithIndex>,
     federation: Federation,
     params: &ProxySearchParams,
+    include_metadata: bool,
 ) -> Result<FederatedSearchResult, ProxySearchError> {
     let url = format!("{}/multi-search", node.url);
 
@@ -119,7 +120,16 @@ pub async fn proxy_search(
     };
 
     for i in 0..params.try_count {
-        match try_proxy_search(&url, search_api_key, &federated, &params.client, deadline).await {
+        match try_proxy_search(
+            &url,
+            search_api_key,
+            &federated,
+            &params.client,
+            deadline,
+            include_metadata,
+        )
+        .await
+        {
             Ok(response) => return Ok(response),
             Err(retry) => {
                 let duration = retry.into_duration(i)?;
@@ -127,7 +137,7 @@ pub async fn proxy_search(
             }
         }
     }
-    try_proxy_search(&url, search_api_key, &federated, &params.client, deadline)
+    try_proxy_search(&url, search_api_key, &federated, &params.client, deadline, include_metadata)
         .await
         .map_err(Retry::into_error)
 }
@@ -138,6 +148,7 @@ async fn try_proxy_search(
     federated: &FederatedSearch,
     client: &Client,
     deadline: std::time::Instant,
+    include_metadata: bool,
 ) -> Result<FederatedSearchResult, Retry> {
     let timeout = deadline.saturating_duration_since(std::time::Instant::now());
 
@@ -148,6 +159,8 @@ async fn try_proxy_search(
         request
     };
     let request = request.header(PROXY_SEARCH_HEADER, PROXY_SEARCH_HEADER_VALUE);
+    let request =
+        if include_metadata { request.header(INCLUDE_METADATA_HEADER, "true") } else { request };
 
     let response = request.send().await;
     let response = match response {

crates/meilisearch/src/search/federated/types.rs

@@ -18,6 +18,8 @@ use serde::{Deserialize, Serialize};
 use utoipa::ToSchema;
 use uuid::Uuid;
 
+use crate::search::SearchMetadata;
+
 use super::super::{ComputedFacets, FacetStats, HitsInfo, SearchHit, SearchQueryWithIndex};
 use crate::milli::vector::Embedding;
 
@@ -134,6 +136,8 @@ pub struct FederatedSearchResult {
     pub facets_by_index: FederatedFacets,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub request_uid: Option<Uuid>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub metadata: Option<Vec<SearchMetadata>>,
 
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub remote_errors: Option<BTreeMap<String, ResponseError>>,
@@ -160,6 +164,7 @@ impl fmt::Debug for FederatedSearchResult {
             facets_by_index,
             remote_errors,
             request_uid,
+            metadata,
         } = self;
 
         let mut debug = f.debug_struct("SearchResult");
@@ -195,6 +200,9 @@ impl fmt::Debug for FederatedSearchResult {
         if let Some(request_uid) = request_uid {
             debug.field("request_uid", &request_uid);
         }
+        if let Some(metadata) = metadata {
+            debug.field("metadata", &metadata);
+        }
 
         debug.finish()
     }

crates/meilisearch/src/search/mod.rs

@@ -57,6 +57,7 @@ pub const DEFAULT_CROP_MARKER: fn() -> String = || "…".to_string();
 pub const DEFAULT_HIGHLIGHT_PRE_TAG: fn() -> String = || "<em>".to_string();
 pub const DEFAULT_HIGHLIGHT_POST_TAG: fn() -> String = || "</em>".to_string();
 pub const DEFAULT_SEMANTIC_RATIO: fn() -> SemanticRatio = || SemanticRatio(0.5);
+pub const INCLUDE_METADATA_HEADER: &str = "Meili-Include-Metadata";
 
 #[derive(Clone, Default, PartialEq, Deserr, ToSchema)]
 #[deserr(error = DeserrJsonError, rename_all = camelCase, deny_unknown_fields)]
@@ -836,6 +837,18 @@ pub struct SearchHit {
     pub ranking_score_details: Option<serde_json::Map<String, serde_json::Value>>,
 }
 
+#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, ToSchema)]
+#[serde(rename_all = "camelCase")]
+#[schema(rename_all = "camelCase")]
+pub struct SearchMetadata {
+    pub query_uid: Uuid,
+    pub index_uid: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub primary_key: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub remote: Option<String>,
+}
+
 #[derive(Serialize, Clone, PartialEq, ToSchema)]
 #[serde(rename_all = "camelCase")]
 #[schema(rename_all = "camelCase")]
@@ -854,6 +867,8 @@ pub struct SearchResult {
     pub facet_stats: Option<BTreeMap<String, FacetStats>>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub request_uid: Option<Uuid>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub metadata: Option<SearchMetadata>,
 
     #[serde(skip_serializing_if = "Option::is_none")]
     pub semantic_hit_count: Option<u32>,
@@ -876,6 +891,7 @@ impl fmt::Debug for SearchResult {
             facet_distribution,
             facet_stats,
             request_uid,
+            metadata,
             semantic_hit_count,
             degraded,
             used_negative_operator,
@@ -908,6 +924,9 @@ impl fmt::Debug for SearchResult {
         if let Some(request_uid) = request_uid {
             debug.field("request_uid", &request_uid);
         }
+        if let Some(metadata) = metadata {
+            debug.field("metadata", &metadata);
+        }
 
         debug.finish()
     }
@@ -1120,16 +1139,28 @@ pub fn prepare_search<'t>(
     Ok((search, is_finite_pagination, max_total_hits, offset))
 }
 
-pub fn perform_search(
+pub struct SearchParams {
-    index_uid: String,
+    pub index_uid: String,
-    index: &Index,
+    pub query: SearchQuery,
-    query: SearchQuery,
+    pub search_kind: SearchKind,
-    search_kind: SearchKind,
+    pub retrieve_vectors: RetrieveVectors,
-    retrieve_vectors: RetrieveVectors,
+    pub features: RoFeatures,
-    features: RoFeatures,
+    pub request_uid: Uuid,
-    request_uid: Uuid,
+    pub include_metadata: bool,
-) -> Result<SearchResult, ResponseError> {
+}
+
+pub fn perform_search(params: SearchParams, index: &Index) -> Result<SearchResult, ResponseError> {
+    let SearchParams {
+        index_uid,
+        query,
+        search_kind,
+        retrieve_vectors,
+        features,
+        request_uid,
+        include_metadata,
+    } = params;
     let before_search = Instant::now();
+    let index_uid_for_metadata = index_uid.clone();
     let rtxn = index.read_txn()?;
     let time_budget = match index.search_cutoff(&rtxn)? {
         Some(cutoff) => TimeBudget::new(Duration::from_millis(cutoff)),
@@ -1150,7 +1181,20 @@ pub fn perform_search(
             query_vector,
         },
         semantic_hit_count,
-    ) = search_from_kind(index_uid, search_kind, search)?;
+    ) = search_from_kind(index_uid.clone(), search_kind, search)?;
+
+    let metadata = if include_metadata {
+        let query_uid = Uuid::now_v7();
+        let primary_key = index.primary_key(&rtxn)?.map(|pk| pk.to_string());
+        Some(SearchMetadata {
+            query_uid,
+            index_uid: index_uid_for_metadata,
+            primary_key,
+            remote: None, // Local searches don't have a remote
+        })
+    } else {
+        None
+    };
 
     let SearchQuery {
         q,
@@ -1233,7 +1277,6 @@ pub fn perform_search(
         .transpose()?
         .map(|ComputedFacets { distribution, stats }| (distribution, stats))
         .unzip();
-
     let result = SearchResult {
         hits: documents,
         hits_info,
@@ -1246,6 +1289,7 @@ pub fn perform_search(
         used_negative_operator,
         semantic_hit_count,
         request_uid: Some(request_uid),
+        metadata,
     };
     Ok(result)
 }

crates/meilisearch/tests/common/index.rs

@@ -516,6 +516,18 @@ impl<State> Index<'_, State> {
         self.service.post_encoded(url, query, self.encoder).await
     }
 
+    pub async fn search_with_headers(
+        &self,
+        query: Value,
+        headers: Vec<(&str, &str)>,
+    ) -> (Value, StatusCode) {
+        let url = format!("/indexes/{}/search", urlencode(self.uid.as_ref()));
+        let body = serde_json::to_string(&query).unwrap();
+        let mut all_headers = vec![("content-type", "application/json")];
+        all_headers.extend(headers);
+        self.service.post_str(url, body, all_headers).await
+    }
+
     pub async fn search_get(&self, query: &str) -> (Value, StatusCode) {
         let url = format!("/indexes/{}/search{}", urlencode(self.uid.as_ref()), query);
         self.service.get(url).await

crates/meilisearch/tests/common/server.rs

@@ -390,6 +390,17 @@ impl<State> Server<State> {
         self.service.post("/multi-search", queries).await
     }
 
+    pub async fn multi_search_with_headers(
+        &self,
+        queries: Value,
+        headers: Vec<(&str, &str)>,
+    ) -> (Value, StatusCode) {
+        let body = serde_json::to_string(&queries).unwrap();
+        let mut all_headers = vec![("content-type", "application/json")];
+        all_headers.extend(headers);
+        self.service.post_str("/multi-search", body, all_headers).await
+    }
+
     pub async fn list_indexes_raw(&self, parameters: &str) -> (Value, StatusCode) {
         self.service.get(format!("/indexes{parameters}")).await
     }

crates/meilisearch/tests/search/metadata.rs

@@ -0,0 +1,387 @@
+use meili_snap::{json_string, snapshot};
+
+use crate::common::{shared_index_with_documents, Server, DOCUMENTS};
+use crate::json;
+
+#[actix_rt::test]
+async fn search_without_metadata_header() {
+    let index = shared_index_with_documents().await;
+
+    // Test that metadata is not included by default
+    index
+        .search(json!({"q": "glass"}), |response, code| {
+            snapshot!(code, @"200 OK");
+            snapshot!(json_string!(response, { ".processingTimeMs" => "[duration]", ".requestUid" => "[uuid]" }), @r###"
+            {
+              "hits": [
+                {
+                  "title": "Gläss",
+                  "id": "450465",
+                  "color": [
+                    "blue",
+                    "red"
+                  ]
+                }
+              ],
+              "query": "glass",
+              "processingTimeMs": "[duration]",
+              "limit": 20,
+              "offset": 0,
+              "estimatedTotalHits": 1,
+              "requestUid": "[uuid]"
+            }
+            "###);
+        })
+        .await;
+}
+
+#[actix_rt::test]
+async fn search_with_metadata_header() {
+    let server = Server::new_shared();
+    let index = server.unique_index();
+
+    let documents = DOCUMENTS.clone();
+    let (task, _code) = index.add_documents(documents, None).await;
+    server.wait_task(task.uid()).await.succeeded();
+
+    // Test with Meili-Include-Metadata header
+    let (response, code) = index
+        .search_with_headers(json!({"q": "glass"}), vec![("Meili-Include-Metadata", "true")])
+        .await;
+
+    snapshot!(code, @"200 OK");
+    snapshot!(json_string!(response, { ".processingTimeMs" => "[duration]", ".requestUid" => "[uuid]", ".metadata.queryUid" => "[uuid]" }), @r###"
+    {
+      "hits": [
+        {
+          "title": "Gläss",
+          "id": "450465",
+          "color": [
+            "blue",
+            "red"
+          ]
+        }
+      ],
+      "query": "glass",
+      "processingTimeMs": "[duration]",
+      "limit": 20,
+      "offset": 0,
+      "estimatedTotalHits": 1,
+      "requestUid": "[uuid]",
+      "metadata": {
+        "queryUid": "[uuid]",
+        "indexUid": "[uuid]",
+        "primaryKey": "id"
+      }
+    }
+    "###);
+}
+
+#[actix_rt::test]
+async fn search_with_metadata_header_and_primary_key() {
+    let server = Server::new_shared();
+    let index = server.unique_index();
+
+    let documents = DOCUMENTS.clone();
+    let (task, _code) = index.add_documents(documents, Some("id")).await;
+    server.wait_task(task.uid()).await.succeeded();
+
+    // Test with Meili-Include-Metadata header
+    let (response, code) = index
+        .search_with_headers(json!({"q": "glass"}), vec![("Meili-Include-Metadata", "true")])
+        .await;
+
+    snapshot!(code, @"200 OK");
+    snapshot!(json_string!(response, { ".processingTimeMs" => "[duration]", ".requestUid" => "[uuid]", ".metadata.queryUid" => "[uuid]" }), @r###"
+    {
+      "hits": [
+        {
+          "id": "450465",
+          "title": "Gläss",
+          "color": [
+            "blue",
+            "red"
+          ]
+        }
+      ],
+      "query": "glass",
+      "processingTimeMs": "[duration]",
+      "limit": 20,
+      "offset": 0,
+      "estimatedTotalHits": 1,
+      "requestUid": "[uuid]",
+      "metadata": {
+        "queryUid": "[uuid]",
+        "indexUid": "[uuid]",
+        "primaryKey": "id"
+      }
+    }
+    "###);
+}
+
+#[actix_rt::test]
+async fn multi_search_without_metadata_header() {
+    let server = Server::new_shared();
+    let index = server.unique_index();
+
+    let documents = DOCUMENTS.clone();
+    let (task, _code) = index.add_documents(documents, None).await;
+    server.wait_task(task.uid()).await.succeeded();
+
+    // Test multi-search without metadata header
+    let (response, code) = server
+        .multi_search(json!({
+            "queries": [
+                {"indexUid": index.uid, "q": "glass"},
+                {"indexUid": index.uid, "q": "dragon"}
+            ]
+        }))
+        .await;
+
+    snapshot!(code, @"200 OK");
+    snapshot!(json_string!(response, { ".results[0].processingTimeMs" => "[duration]", ".results[0].requestUid" => "[uuid]", ".results[1].processingTimeMs" => "[duration]", ".results[1].requestUid" => "[uuid]" }), @r###"
+    {
+      "results": [
+        {
+          "indexUid": "[uuid]",
+          "hits": [
+            {
+              "title": "Gläss",
+              "id": "450465",
+              "color": [
+                "blue",
+                "red"
+              ]
+            }
+          ],
+          "query": "glass",
+          "processingTimeMs": "[duration]",
+          "limit": 20,
+          "offset": 0,
+          "estimatedTotalHits": 1,
+          "requestUid": "[uuid]"
+        },
+        {
+          "indexUid": "[uuid]",
+          "hits": [
+            {
+              "title": "How to Train Your Dragon: The Hidden World",
+              "id": "166428",
+              "color": [
+                "green",
+                "red"
+              ]
+            }
+          ],
+          "query": "dragon",
+          "processingTimeMs": "[duration]",
+          "limit": 20,
+          "offset": 0,
+          "estimatedTotalHits": 1,
+          "requestUid": "[uuid]"
+        }
+      ]
+    }
+    "###);
+}
+
+#[actix_rt::test]
+async fn multi_search_with_metadata_header() {
+    let server = Server::new_shared();
+    let index = server.unique_index();
+
+    let documents = DOCUMENTS.clone();
+    let (task, _code) = index.add_documents(documents, Some("id")).await;
+    server.wait_task(task.uid()).await.succeeded();
+
+    // Test multi-search with metadata header
+    let (response, code) = server
+        .multi_search_with_headers(
+            json!({
+                "queries": [
+                    {"indexUid": index.uid, "q": "glass"},
+                    {"indexUid": index.uid, "q": "dragon"}
+                ]
+            }),
+            vec![("Meili-Include-Metadata", "true")],
+        )
+        .await;
+
+    snapshot!(code, @"200 OK");
+    snapshot!(json_string!(response, { ".results[0].processingTimeMs" => "[duration]", ".results[0].requestUid" => "[uuid]", ".results[0].metadata.queryUid" => "[uuid]", ".results[1].processingTimeMs" => "[duration]", ".results[1].requestUid" => "[uuid]", ".results[1].metadata.queryUid" => "[uuid]" }), @r###"
+    {
+      "results": [
+        {
+          "indexUid": "[uuid]",
+          "hits": [
+            {
+              "id": "450465",
+              "title": "Gläss",
+              "color": [
+                "blue",
+                "red"
+              ]
+            }
+          ],
+          "query": "glass",
+          "processingTimeMs": "[duration]",
+          "limit": 20,
+          "offset": 0,
+          "estimatedTotalHits": 1,
+          "requestUid": "[uuid]",
+          "metadata": {
+            "queryUid": "[uuid]",
+            "indexUid": "[uuid]",
+            "primaryKey": "id"
+          }
+        },
+        {
+          "indexUid": "[uuid]",
+          "hits": [
+            {
+              "id": "166428",
+              "title": "How to Train Your Dragon: The Hidden World",
+              "color": [
+                "green",
+                "red"
+              ]
+            }
+          ],
+          "query": "dragon",
+          "processingTimeMs": "[duration]",
+          "limit": 20,
+          "offset": 0,
+          "estimatedTotalHits": 1,
+          "requestUid": "[uuid]",
+          "metadata": {
+            "queryUid": "[uuid]",
+            "indexUid": "[uuid]",
+            "primaryKey": "id"
+          }
+        }
+      ]
+    }
+    "###);
+}
+
+#[actix_rt::test]
+async fn search_metadata_header_false_value() {
+    let server = Server::new_shared();
+    let index = server.unique_index();
+
+    let documents = DOCUMENTS.clone();
+    let (task, _code) = index.add_documents(documents, None).await;
+    server.wait_task(task.uid()).await.succeeded();
+
+    // Test with header set to false
+    let (response, code) = index
+        .search_with_headers(json!({"q": "glass"}), vec![("Meili-Include-Metadata", "false")])
+        .await;
+
+    snapshot!(code, @"200 OK");
+    snapshot!(json_string!(response, { ".processingTimeMs" => "[duration]", ".requestUid" => "[uuid]" }), @r###"
+    {
+      "hits": [
+        {
+          "title": "Gläss",
+          "id": "450465",
+          "color": [
+            "blue",
+            "red"
+          ]
+        }
+      ],
+      "query": "glass",
+      "processingTimeMs": "[duration]",
+      "limit": 20,
+      "offset": 0,
+      "estimatedTotalHits": 1,
+      "requestUid": "[uuid]"
+    }
+    "###);
+}
+
+#[actix_rt::test]
+async fn search_metadata_uuid_format() {
+    let server = Server::new_shared();
+    let index = server.unique_index();
+
+    let documents = DOCUMENTS.clone();
+    let (task, _code) = index.add_documents(documents, None).await;
+    server.wait_task(task.uid()).await.succeeded();
+
+    let (response, code) = index
+        .search_with_headers(json!({"q": "glass"}), vec![("Meili-Include-Metadata", "true")])
+        .await;
+
+    snapshot!(code, @"200 OK");
+    snapshot!(json_string!(response, { ".processingTimeMs" => "[duration]", ".requestUid" => "[uuid]", ".metadata.queryUid" => "[uuid]" }), @r###"
+    {
+      "hits": [
+        {
+          "title": "Gläss",
+          "id": "450465",
+          "color": [
+            "blue",
+            "red"
+          ]
+        }
+      ],
+      "query": "glass",
+      "processingTimeMs": "[duration]",
+      "limit": 20,
+      "offset": 0,
+      "estimatedTotalHits": 1,
+      "requestUid": "[uuid]",
+      "metadata": {
+        "queryUid": "[uuid]",
+        "indexUid": "[uuid]",
+        "primaryKey": "id"
+      }
+    }
+    "###);
+}
+
+#[actix_rt::test]
+async fn search_metadata_consistency_across_requests() {
+    let server = Server::new_shared();
+    let index = server.unique_index();
+
+    let documents = DOCUMENTS.clone();
+    let (task, _code) = index.add_documents(documents, Some("id")).await;
+    server.wait_task(task.uid()).await.succeeded();
+
+    // Make multiple requests and check that metadata is consistent
+    for _i in 0..3 {
+        let (response, code) = index
+            .search_with_headers(json!({"q": "glass"}), vec![("Meili-Include-Metadata", "true")])
+            .await;
+
+        snapshot!(code, @"200 OK");
+        snapshot!(json_string!(response, { ".processingTimeMs" => "[duration]", ".requestUid" => "[uuid]", ".metadata.queryUid" => "[uuid]" }), @r###"
+        {
+          "hits": [
+            {
+              "id": "450465",
+              "title": "Gläss",
+              "color": [
+                "blue",
+                "red"
+              ]
+            }
+          ],
+          "query": "glass",
+          "processingTimeMs": "[duration]",
+          "limit": 20,
+          "offset": 0,
+          "estimatedTotalHits": 1,
+          "requestUid": "[uuid]",
+          "metadata": {
+            "queryUid": "[uuid]",
+            "indexUid": "[uuid]",
+            "primaryKey": "id"
+          }
+        }
+        "###);
+    }
+}

crates/meilisearch/tests/search/mod.rs

@@ -11,6 +11,7 @@ mod hybrid;
 #[cfg(not(feature = "chinese-pinyin"))]
 mod locales;
 mod matching_strategy;
+mod metadata;
 mod multi;
 mod pagination;
 mod restrict_searchable;

crates/meilisearch/tests/upgrade/mod.rs

@@ -43,7 +43,7 @@ async fn version_too_old() {
     std::fs::write(db_path.join("VERSION"), "1.11.9999").unwrap();
     let options = Opt { experimental_dumpless_upgrade: true, ..default_settings };
     let err = Server::new_with_options(options).await.map(|_| ()).unwrap_err();
-    snapshot!(err, @"Database version 1.11.9999 is too old for the experimental dumpless upgrade feature. Please generate a dump using the v1.11.9999 and import it in the v1.23.0");
+    snapshot!(err, @"Database version 1.11.9999 is too old for the experimental dumpless upgrade feature. Please generate a dump using the v1.11.9999 and import it in the v1.24.0");
 }
 
 #[actix_rt::test]
@@ -58,7 +58,7 @@ async fn version_requires_downgrade() {
     std::fs::write(db_path.join("VERSION"), format!("{major}.{minor}.{patch}")).unwrap();
     let options = Opt { experimental_dumpless_upgrade: true, ..default_settings };
     let err = Server::new_with_options(options).await.map(|_| ()).unwrap_err();
-    snapshot!(err, @"Database version 1.23.1 is higher than the Meilisearch version 1.23.0. Downgrade is not supported");
+    snapshot!(err, @"Database version 1.24.1 is higher than the Meilisearch version 1.24.0. Downgrade is not supported");
 }
 
 #[actix_rt::test]

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/batches_filter_afterEnqueuedAt_equal_2025-01-16T16_47_41.snap

@@ -8,7 +8,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "progress": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "stats": {
         "totalNbTasks": 1,

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/batches_filter_afterFinishedAt_equal_2025-01-16T16_47_41.snap

@@ -8,7 +8,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "progress": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "stats": {
         "totalNbTasks": 1,

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/batches_filter_afterStartedAt_equal_2025-01-16T16_47_41.snap

@@ -8,7 +8,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "progress": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "stats": {
         "totalNbTasks": 1,

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/tasks_filter_afterEnqueuedAt_equal_2025-01-16T16_47_41.snap

@@ -12,7 +12,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "canceledBy": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "error": null,
       "duration": "[duration]",

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/tasks_filter_afterFinishedAt_equal_2025-01-16T16_47_41.snap

@@ -12,7 +12,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "canceledBy": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "error": null,
       "duration": "[duration]",

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/tasks_filter_afterStartedAt_equal_2025-01-16T16_47_41.snap

@@ -12,7 +12,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "canceledBy": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "error": null,
       "duration": "[duration]",

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/the_whole_batch_queue_once_everything_has_been_processed.snap

@@ -8,7 +8,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "progress": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "stats": {
         "totalNbTasks": 1,

crates/meilisearch/tests/upgrade/v1_12/snapshots/v1_12_0.rs/check_the_index_scheduler/the_whole_task_queue_once_everything_has_been_processed.snap

@@ -12,7 +12,7 @@ source: crates/meilisearch/tests/upgrade/v1_12/v1_12_0.rs
       "canceledBy": null,
       "details": {
         "upgradeFrom": "v1.12.0",
-        "upgradeTo": "v1.23.0"
+        "upgradeTo": "v1.24.0"
       },
       "error": null,
       "duration": "[duration]",

crates/milli/Cargo.toml

@@ -90,7 +90,7 @@ rhai = { version = "1.22.2", features = [
     "sync",
 ] }
 arroy = "0.6.4-nested-rtxns"
-hannoy = { version = "0.0.9-nested-rtxns", features = ["arroy"] }
+hannoy = { version = "0.0.9-nested-rtxns-2", features = ["arroy"] }
 rand = "0.8.5"
 tracing = "0.1.41"
 ureq = { version = "2.12.1", features = ["json"] }

crates/milli/src/search/new/bucket_sort.rs

@@ -97,7 +97,7 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
 
     logger.start_iteration_ranking_rule(0, ranking_rules[0].as_ref(), query, universe);
 
-    ranking_rules[0].start_iteration(ctx, logger, universe, query)?;
+    ranking_rules[0].start_iteration(ctx, logger, universe, query, &time_budget)?;
 
     let mut ranking_rule_scores: Vec<ScoreDetails> = vec![];
 
@@ -168,42 +168,6 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
         };
 
     while valid_docids.len() < max_len_to_evaluate {
-        if time_budget.exceeded() {
-            loop {
-                let bucket = std::mem::take(&mut ranking_rule_universes[cur_ranking_rule_index]);
-                ranking_rule_scores.push(ScoreDetails::Skipped);
-
-                // remove candidates from the universe without adding them to result if their score is below the threshold
-                let is_below_threshold =
-                    ranking_score_threshold.is_some_and(|ranking_score_threshold| {
-                        let current_score = ScoreDetails::global_score(ranking_rule_scores.iter());
-                        current_score < ranking_score_threshold
-                    });
-
-                if is_below_threshold {
-                    all_candidates -= &bucket;
-                    all_candidates -= &ranking_rule_universes[cur_ranking_rule_index];
-                } else {
-                    maybe_add_to_results!(bucket);
-                }
-
-                ranking_rule_scores.pop();
-
-                if cur_ranking_rule_index == 0 {
-                    break;
-                }
-
-                back!();
-            }
-
-            return Ok(BucketSortOutput {
-                scores: valid_scores,
-                docids: valid_docids,
-                all_candidates,
-                degraded: true,
-            });
-        }
-
         // The universe for this bucket is zero, so we don't need to sort
         // anything, just go back to the parent ranking rule.
         if ranking_rule_universes[cur_ranking_rule_index].is_empty()
@@ -216,14 +180,63 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
             continue;
         }
 
-        let Some(next_bucket) = ranking_rules[cur_ranking_rule_index].next_bucket(
+        let next_bucket = if time_budget.exceeded() {
-            ctx,
+            match ranking_rules[cur_ranking_rule_index].non_blocking_next_bucket(
-            logger,
+                ctx,
-            &ranking_rule_universes[cur_ranking_rule_index],
+                logger,
-        )?
+                &ranking_rule_universes[cur_ranking_rule_index],
-        else {
+            )? {
-            back!();
+                std::task::Poll::Ready(bucket) => bucket,
-            continue;
+                std::task::Poll::Pending => {
+                    loop {
+                        let bucket =
+                            std::mem::take(&mut ranking_rule_universes[cur_ranking_rule_index]);
+                        ranking_rule_scores.push(ScoreDetails::Skipped);
+
+                        // remove candidates from the universe without adding them to result if their score is below the threshold
+                        let is_below_threshold =
+                            ranking_score_threshold.is_some_and(|ranking_score_threshold| {
+                                let current_score =
+                                    ScoreDetails::global_score(ranking_rule_scores.iter());
+                                current_score < ranking_score_threshold
+                            });
+
+                        if is_below_threshold {
+                            all_candidates -= &bucket;
+                            all_candidates -= &ranking_rule_universes[cur_ranking_rule_index];
+                        } else {
+                            maybe_add_to_results!(bucket);
+                        }
+
+                        ranking_rule_scores.pop();
+
+                        if cur_ranking_rule_index == 0 {
+                            break;
+                        }
+
+                        back!();
+                    }
+
+                    return Ok(BucketSortOutput {
+                        scores: valid_scores,
+                        docids: valid_docids,
+                        all_candidates,
+                        degraded: true,
+                    });
+                }
+            }
+        } else {
+            let Some(next_bucket) = ranking_rules[cur_ranking_rule_index].next_bucket(
+                ctx,
+                logger,
+                &ranking_rule_universes[cur_ranking_rule_index],
+                &time_budget,
+            )?
+            else {
+                back!();
+                continue;
+            };
+            next_bucket
         };
 
         ranking_rule_scores.push(next_bucket.score);
@@ -275,6 +288,7 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
             logger,
             &next_bucket.candidates,
             &next_bucket.query,
+            &time_budget,
         )?;
     }
 

crates/milli/src/search/new/exact_attribute.rs

@@ -6,7 +6,7 @@ use super::ranking_rules::{RankingRule, RankingRuleOutput};
 use crate::score_details::{self, ScoreDetails};
 use crate::search::new::query_graph::QueryNodeData;
 use crate::search::new::query_term::ExactTerm;
-use crate::{CboRoaringBitmapCodec, Result, SearchContext, SearchLogger};
+use crate::{CboRoaringBitmapCodec, Result, SearchContext, SearchLogger, TimeBudget};
 
 /// A ranking rule that produces 3 disjoint buckets:
 ///
@@ -35,6 +35,7 @@ impl<'ctx> RankingRule<'ctx, QueryGraph> for ExactAttribute {
         _logger: &mut dyn SearchLogger<QueryGraph>,
         universe: &roaring::RoaringBitmap,
         query: &QueryGraph,
+        _time_budget: &TimeBudget,
     ) -> Result<()> {
         self.state = State::start_iteration(ctx, universe, query)?;
         Ok(())
@@ -46,6 +47,7 @@ impl<'ctx> RankingRule<'ctx, QueryGraph> for ExactAttribute {
         _ctx: &mut SearchContext<'ctx>,
         _logger: &mut dyn SearchLogger<QueryGraph>,
         universe: &roaring::RoaringBitmap,
+        _time_budget: &TimeBudget,
     ) -> Result<Option<RankingRuleOutput<QueryGraph>>> {
         let state = std::mem::take(&mut self.state);
         let (state, output) = State::next(state, universe);

crates/milli/src/search/new/geo_sort.rs

@@ -7,7 +7,7 @@ use super::ranking_rules::{RankingRule, RankingRuleOutput, RankingRuleQueryTrait
 use crate::documents::geo_sort::{fill_cache, next_bucket};
 use crate::documents::{GeoSortParameter, GeoSortStrategy};
 use crate::score_details::{self, ScoreDetails};
-use crate::{GeoPoint, Result, SearchContext, SearchLogger};
+use crate::{GeoPoint, Result, SearchContext, SearchLogger, TimeBudget};
 
 pub struct GeoSort<Q: RankingRuleQueryTrait> {
     query: Option<Q>,
@@ -84,6 +84,7 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for GeoSort<Q> {
         _logger: &mut dyn SearchLogger<Q>,
         universe: &RoaringBitmap,
         query: &Q,
+        _time_budget: &TimeBudget,
     ) -> Result<()> {
         assert!(self.query.is_none());
 
@@ -110,6 +111,7 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for GeoSort<Q> {
         ctx: &mut SearchContext<'ctx>,
         _logger: &mut dyn SearchLogger<Q>,
         universe: &RoaringBitmap,
+        _time_budget: &TimeBudget,
     ) -> Result<Option<RankingRuleOutput<Q>>> {
         let query = self.query.as_ref().unwrap().clone();
 

crates/milli/src/search/new/graph_based_ranking_rule.rs

@@ -53,7 +53,7 @@ use super::{QueryGraph, RankingRule, RankingRuleOutput, SearchContext};
 use crate::score_details::Rank;
 use crate::search::new::query_term::LocatedQueryTermSubset;
 use crate::search::new::ranking_rule_graph::PathVisitor;
-use crate::{Result, TermsMatchingStrategy};
+use crate::{Result, TermsMatchingStrategy, TimeBudget};
 
 pub type Words = GraphBasedRankingRule<WordsGraph>;
 impl GraphBasedRankingRule<WordsGraph> {
@@ -135,6 +135,7 @@ impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBase
         _logger: &mut dyn SearchLogger<QueryGraph>,
         _universe: &RoaringBitmap,
         query_graph: &QueryGraph,
+        _time_budget: &TimeBudget,
     ) -> Result<()> {
         // the `next_max_cost` is the successor integer to the maximum cost of the paths in the graph.
         //
@@ -217,6 +218,7 @@ impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBase
         ctx: &mut SearchContext<'ctx>,
         logger: &mut dyn SearchLogger<QueryGraph>,
         universe: &RoaringBitmap,
+        _time_budget: &TimeBudget,
     ) -> Result<Option<RankingRuleOutput<QueryGraph>>> {
         // Will crash if `next_bucket` is called before `start_iteration` or after `end_iteration`,
         // should never happen

crates/milli/src/search/new/ranking_rules.rs

@@ -1,9 +1,11 @@
+use std::task::Poll;
+
 use roaring::RoaringBitmap;
 
 use super::logger::SearchLogger;
 use super::{QueryGraph, SearchContext};
 use crate::score_details::ScoreDetails;
-use crate::Result;
+use crate::{Result, TimeBudget};
 
 /// An internal trait implemented by only [`PlaceholderQuery`] and [`QueryGraph`]
 pub trait RankingRuleQueryTrait: Sized + Clone + 'static {}
@@ -28,12 +30,15 @@ pub trait RankingRule<'ctx, Query: RankingRuleQueryTrait> {
     /// buckets using [`next_bucket`](RankingRule::next_bucket).
     ///
     /// The given universe is the universe that will be given to [`next_bucket`](RankingRule::next_bucket).
+    ///
+    /// If this function may take a long time, it should check the `time_budget` and return early if exceeded.
     fn start_iteration(
         &mut self,
         ctx: &mut SearchContext<'ctx>,
         logger: &mut dyn SearchLogger<Query>,
         universe: &RoaringBitmap,
         query: &Query,
+        time_budget: &TimeBudget,
     ) -> Result<()>;
 
     /// Return the next bucket of this ranking rule.
@@ -43,13 +48,31 @@ pub trait RankingRule<'ctx, Query: RankingRuleQueryTrait> {
     /// The universe given as argument is either:
     /// - a subset of the universe given to the previous call to [`next_bucket`](RankingRule::next_bucket); OR
     /// - the universe given to [`start_iteration`](RankingRule::start_iteration)
+    ///
+    /// If this function may take a long time, it should check the `time_budget` and return early if exceeded.
     fn next_bucket(
         &mut self,
         ctx: &mut SearchContext<'ctx>,
         logger: &mut dyn SearchLogger<Query>,
         universe: &RoaringBitmap,
+        time_budget: &TimeBudget,
     ) -> Result<Option<RankingRuleOutput<Query>>>;
 
+    /// Return the next bucket of this ranking rule, if doing so can be done without blocking
+    ///
+    /// Even if the time budget is exceeded, when getting the next bucket is a fast operation, this should return `true`
+    /// to allow Meilisearch to collect the results.
+    ///
+    /// Default implementation conservatively returns that it would block.
+    fn non_blocking_next_bucket(
+        &mut self,
+        _ctx: &mut SearchContext<'ctx>,
+        _logger: &mut dyn SearchLogger<Query>,
+        _universe: &RoaringBitmap,
+    ) -> Result<Poll<RankingRuleOutput<Query>>> {
+        Ok(Poll::Pending)
+    }
+
     /// Finish iterating over the buckets, which yields control to the parent ranking rule
     /// The next call to this ranking rule, if any, will be [`start_iteration`](RankingRule::start_iteration).
     fn end_iteration(

crates/milli/src/search/new/sort.rs

@@ -7,7 +7,7 @@ use crate::heed_codec::facet::{FacetGroupKeyCodec, OrderedF64Codec};
 use crate::heed_codec::{BytesRefCodec, StrRefCodec};
 use crate::score_details::{self, ScoreDetails};
 use crate::search::facet::{ascending_facet_sort, descending_facet_sort};
-use crate::{FieldId, Index, Result};
+use crate::{FieldId, Index, Result, TimeBudget};
 
 pub trait RankingRuleOutputIter<'ctx, Query> {
     fn next_bucket(&mut self) -> Result<Option<RankingRuleOutput<Query>>>;
@@ -96,6 +96,7 @@ impl<'ctx, Query: RankingRuleQueryTrait> RankingRule<'ctx, Query> for Sort<'ctx,
         _logger: &mut dyn SearchLogger<Query>,
         parent_candidates: &RoaringBitmap,
         parent_query: &Query,
+        _time_budget: &TimeBudget,
     ) -> Result<()> {
         let iter: RankingRuleOutputIterWrapper<'ctx, Query> = match self.field_id {
             Some(field_id) => {
@@ -194,6 +195,7 @@ impl<'ctx, Query: RankingRuleQueryTrait> RankingRule<'ctx, Query> for Sort<'ctx,
         _ctx: &mut SearchContext<'ctx>,
         _logger: &mut dyn SearchLogger<Query>,
         universe: &RoaringBitmap,
+        _time_budget: &TimeBudget,
     ) -> Result<Option<RankingRuleOutput<Query>>> {
         let iter = self.iter.as_mut().unwrap();
         if let Some(mut bucket) = iter.next_bucket()? {

crates/milli/src/search/new/tests/cutoff.rs

@@ -3,12 +3,17 @@
 //! 2. A test that ensure the filters are affectively applied even with a cutoff of 0
 //! 3. A test that ensure the cutoff works well with the ranking scores
 
+use std::collections::BTreeMap;
+use std::sync::Arc;
 use std::time::Duration;
 
 use meili_snap::snapshot;
 
 use crate::index::tests::TempIndex;
 use crate::score_details::{ScoreDetails, ScoringStrategy};
+use crate::update::Setting;
+use crate::vector::settings::EmbeddingSettings;
+use crate::vector::{Embedder, EmbedderOptions};
 use crate::{Criterion, Filter, FilterableAttributesRule, Search, TimeBudget};
 
 fn create_index() -> TempIndex {
@@ -361,9 +366,8 @@ fn degraded_search_and_score_details() {
     ]
     "###);
 
-    // After SIX loop iteration. The words ranking rule gave us a new bucket.
+    // After FIVE loop iterations. The words ranking rule gave us a new bucket.
-    // Since we reached the limit we were able to early exit without checking the typo ranking rule.
+    search.time_budget(TimeBudget::max().with_stop_after(5));
-    search.time_budget(TimeBudget::max().with_stop_after(6));
 
     let result = search.execute().unwrap();
     snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
@@ -424,4 +428,399 @@ fn degraded_search_and_score_details() {
         ],
     ]
     "###);
+
+    // After SIX loop iterations.
+    // we finished
+    search.time_budget(TimeBudget::max().with_stop_after(6));
+
+    let result = search.execute().unwrap();
+    snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
+    IDs: [4, 1, 0, 3]
+    Scores: 1.0000 0.9167 0.8333 0.6667 
+    Score Details:
+    [
+        [
+            Words(
+                Words {
+                    matching_words: 3,
+                    max_matching_words: 3,
+                },
+            ),
+            Typo(
+                Typo {
+                    typo_count: 0,
+                    max_typo_count: 3,
+                },
+            ),
+        ],
+        [
+            Words(
+                Words {
+                    matching_words: 3,
+                    max_matching_words: 3,
+                },
+            ),
+            Typo(
+                Typo {
+                    typo_count: 1,
+                    max_typo_count: 3,
+                },
+            ),
+        ],
+        [
+            Words(
+                Words {
+                    matching_words: 3,
+                    max_matching_words: 3,
+                },
+            ),
+            Typo(
+                Typo {
+                    typo_count: 2,
+                    max_typo_count: 3,
+                },
+            ),
+        ],
+        [
+            Words(
+                Words {
+                    matching_words: 2,
+                    max_matching_words: 3,
+                },
+            ),
+            Typo(
+                Typo {
+                    typo_count: 0,
+                    max_typo_count: 2,
+                },
+            ),
+        ],
+    ]
+    "###);
+}
+
+#[test]
+fn degraded_search_and_score_details_vector() {
+    let index = create_index();
+
+    index
+        .add_documents(documents!([
+            {
+                "id": 4,
+                "text": "hella puppo kefir",
+                "_vectors": {
+                    "default": [0.1, 0.1]
+                }
+            },
+            {
+                "id": 3,
+                "text": "hella puppy kefir",
+                "_vectors": {
+                    "default": [-0.1, 0.1]
+                }
+            },
+            {
+                "id": 2,
+                "text": "hello",
+                "_vectors": {
+                    "default": [0.1, -0.1]
+                }
+            },
+            {
+                "id": 1,
+                "text": "hello puppy",
+                "_vectors": {
+                    "default": [-0.1, -0.1]
+                }
+            },
+            {
+                "id": 0,
+                "text": "hello puppy kefir",
+                "_vectors": {
+                    "default": null
+                }
+            },
+        ]))
+        .unwrap();
+
+    index
+        .update_settings(|settings| {
+            let mut embedders = BTreeMap::new();
+            embedders.insert(
+                "default".into(),
+                Setting::Set(EmbeddingSettings {
+                    source: Setting::Set(crate::vector::settings::EmbedderSource::UserProvided),
+                    dimensions: Setting::Set(2),
+                    ..Default::default()
+                }),
+            );
+            settings.set_embedder_settings(embedders);
+            settings.set_vector_store(crate::vector::VectorStoreBackend::Hannoy);
+        })
+        .unwrap();
+
+    let rtxn = index.read_txn().unwrap();
+    let mut search = Search::new(&rtxn, &index);
+
+    let embedder = Arc::new(
+        Embedder::new(
+            EmbedderOptions::UserProvided(crate::vector::embedder::manual::EmbedderOptions {
+                dimensions: 2,
+                distribution: None,
+            }),
+            0,
+        )
+        .unwrap(),
+    );
+
+    search.semantic("default".into(), embedder, false, Some(vec![1., -1.]), None);
+
+    search.limit(4);
+    search.scoring_strategy(ScoringStrategy::Detailed);
+    search.time_budget(TimeBudget::max());
+
+    let result = search.execute().unwrap();
+    snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
+    IDs: [2, 0, 3, 1]
+    Scores: 1.0000 0.5000 0.5000 0.0000 
+    Score Details:
+    [
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        1.0,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.0,
+                    ),
+                },
+            ),
+        ],
+    ]
+    "###);
+
+    // Do ONE loop iteration. Not much can be deduced, almost everyone matched the words first bucket.
+    search.time_budget(TimeBudget::max().with_stop_after(1));
+
+    let result = search.execute().unwrap();
+    snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
+    IDs: [0, 1, 2, 3]
+    Scores: 0.5000 0.0000 0.0000 0.0000 
+    Score Details:
+    [
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Skipped,
+        ],
+        [
+            Skipped,
+        ],
+        [
+            Skipped,
+        ],
+    ]
+    "###);
+
+    search.time_budget(TimeBudget::max().with_stop_after(2));
+
+    let result = search.execute().unwrap();
+    snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
+    IDs: [0, 1, 2, 3]
+    Scores: 0.5000 0.0000 0.0000 0.0000 
+    Score Details:
+    [
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.0,
+                    ),
+                },
+            ),
+        ],
+        [
+            Skipped,
+        ],
+        [
+            Skipped,
+        ],
+    ]
+    "###);
+
+    search.time_budget(TimeBudget::max().with_stop_after(3));
+
+    let result = search.execute().unwrap();
+    snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
+    IDs: [2, 0, 1, 3]
+    Scores: 1.0000 0.5000 0.0000 0.0000 
+    Score Details:
+    [
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        1.0,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.0,
+                    ),
+                },
+            ),
+        ],
+        [
+            Skipped,
+        ],
+    ]
+    "###);
+
+    search.time_budget(TimeBudget::max().with_stop_after(4));
+
+    let result = search.execute().unwrap();
+    snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
+    IDs: [2, 0, 3, 1]
+    Scores: 1.0000 0.5000 0.5000 0.0000 
+    Score Details:
+    [
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        1.0,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.0,
+                    ),
+                },
+            ),
+        ],
+    ]
+    "###);
+
+    search.time_budget(TimeBudget::max().with_stop_after(5));
+
+    let result = search.execute().unwrap();
+    snapshot!(format!("IDs: {:?}\nScores: {}\nScore Details:\n{:#?}", result.documents_ids, result.document_scores.iter().map(|scores| format!("{:.4} ", ScoreDetails::global_score(scores.iter()))).collect::<String>(), result.document_scores), @r###"
+    IDs: [2, 0, 3, 1]
+    Scores: 1.0000 0.5000 0.5000 0.0000 
+    Score Details:
+    [
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        1.0,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.5,
+                    ),
+                },
+            ),
+        ],
+        [
+            Vector(
+                Vector {
+                    similarity: Some(
+                        0.0,
+                    ),
+                },
+            ),
+        ],
+    ]
+    "###);
 }

crates/milli/src/search/new/vector_sort.rs

@@ -1,4 +1,5 @@
 use std::iter::FromIterator;
+use std::task::Poll;
 use std::time::Instant;
 
 use roaring::RoaringBitmap;
@@ -7,7 +8,7 @@ use super::ranking_rules::{RankingRule, RankingRuleOutput, RankingRuleQueryTrait
 use super::VectorStoreStats;
 use crate::score_details::{self, ScoreDetails};
 use crate::vector::{DistributionShift, Embedder, VectorStore};
-use crate::{DocumentId, Result, SearchContext, SearchLogger};
+use crate::{DocumentId, Result, SearchContext, SearchLogger, TimeBudget};
 
 pub struct VectorSort<Q: RankingRuleQueryTrait> {
     query: Option<Q>,
@@ -52,6 +53,7 @@ impl<Q: RankingRuleQueryTrait> VectorSort<Q> {
         &mut self,
         ctx: &mut SearchContext<'_>,
         vector_candidates: &RoaringBitmap,
+        time_budget: &TimeBudget,
     ) -> Result<()> {
         let target = &self.target;
         let backend = ctx.index.get_vector_store(ctx.txn)?.unwrap_or_default();
@@ -59,7 +61,13 @@ impl<Q: RankingRuleQueryTrait> VectorSort<Q> {
         let before = Instant::now();
         let reader =
             VectorStore::new(backend, ctx.index.vector_store, self.embedder_index, self.quantized);
-        let results = reader.nns_by_vector(ctx.txn, target, self.limit, Some(vector_candidates))?;
+        let results = reader.nns_by_vector(
+            ctx.txn,
+            target,
+            self.limit,
+            Some(vector_candidates),
+            time_budget,
+        )?;
         self.cached_sorted_docids = results.into_iter();
         *ctx.vector_store_stats.get_or_insert_default() += VectorStoreStats {
             total_time: before.elapsed(),
@@ -69,6 +77,20 @@ impl<Q: RankingRuleQueryTrait> VectorSort<Q> {
 
         Ok(())
     }
+
+    fn next_result(&mut self, vector_candidates: &RoaringBitmap) -> Option<(DocumentId, f32)> {
+        for (docid, distance) in self.cached_sorted_docids.by_ref() {
+            if vector_candidates.contains(docid) {
+                let score = 1.0 - distance;
+                let score = self
+                    .distribution_shift
+                    .map(|distribution| distribution.shift(score))
+                    .unwrap_or(score);
+                return Some((docid, score));
+            }
+        }
+        None
+    }
 }
 
 impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for VectorSort<Q> {
@@ -83,12 +105,13 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for VectorSort<Q> {
         _logger: &mut dyn SearchLogger<Q>,
         universe: &RoaringBitmap,
         query: &Q,
+        time_budget: &TimeBudget,
     ) -> Result<()> {
         assert!(self.query.is_none());
 
         self.query = Some(query.clone());
         let vector_candidates = &self.vector_candidates & universe;
-        self.fill_buffer(ctx, &vector_candidates)?;
+        self.fill_buffer(ctx, &vector_candidates, time_budget)?;
         Ok(())
     }
 
@@ -99,6 +122,7 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for VectorSort<Q> {
         ctx: &mut SearchContext<'ctx>,
         _logger: &mut dyn SearchLogger<Q>,
         universe: &RoaringBitmap,
+        time_budget: &TimeBudget,
     ) -> Result<Option<RankingRuleOutput<Q>>> {
         let query = self.query.as_ref().unwrap().clone();
         let vector_candidates = &self.vector_candidates & universe;
@@ -111,24 +135,17 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for VectorSort<Q> {
             }));
         }
 
-        for (docid, distance) in self.cached_sorted_docids.by_ref() {
+        if let Some((docid, score)) = self.next_result(&vector_candidates) {
-            if vector_candidates.contains(docid) {
+            return Ok(Some(RankingRuleOutput {
-                let score = 1.0 - distance;
+                query,
-                let score = self
+                candidates: RoaringBitmap::from_iter([docid]),
-                    .distribution_shift
+                score: ScoreDetails::Vector(score_details::Vector { similarity: Some(score) }),
-                    .map(|distribution| distribution.shift(score))
+            }));
-                    .unwrap_or(score);
-                return Ok(Some(RankingRuleOutput {
-                    query,
-                    candidates: RoaringBitmap::from_iter([docid]),
-                    score: ScoreDetails::Vector(score_details::Vector { similarity: Some(score) }),
-                }));
-            }
         }
 
         // if we got out of this loop it means we've exhausted our cache.
         // we need to refill it and run the function again.
-        self.fill_buffer(ctx, &vector_candidates)?;
+        self.fill_buffer(ctx, &vector_candidates, time_budget)?;
 
         // we tried filling the buffer, but it remained empty 😢
         // it means we don't actually have any document remaining in the universe with a vector.
@@ -141,11 +158,39 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for VectorSort<Q> {
             }));
         }
 
-        self.next_bucket(ctx, _logger, universe)
+        self.next_bucket(ctx, _logger, universe, time_budget)
     }
 
     #[tracing::instrument(level = "trace", skip_all, target = "search::vector_sort")]
     fn end_iteration(&mut self, _ctx: &mut SearchContext<'ctx>, _logger: &mut dyn SearchLogger<Q>) {
         self.query = None;
     }
+
+    fn non_blocking_next_bucket(
+        &mut self,
+        _ctx: &mut SearchContext<'ctx>,
+        _logger: &mut dyn SearchLogger<Q>,
+        universe: &RoaringBitmap,
+    ) -> Result<Poll<RankingRuleOutput<Q>>> {
+        let query = self.query.as_ref().unwrap().clone();
+        let vector_candidates = &self.vector_candidates & universe;
+
+        if vector_candidates.is_empty() {
+            return Ok(Poll::Ready(RankingRuleOutput {
+                query,
+                candidates: universe.clone(),
+                score: ScoreDetails::Vector(score_details::Vector { similarity: None }),
+            }));
+        }
+
+        if let Some((docid, score)) = self.next_result(&vector_candidates) {
+            Ok(Poll::Ready(RankingRuleOutput {
+                query,
+                candidates: RoaringBitmap::from_iter([docid]),
+                score: ScoreDetails::Vector(score_details::Vector { similarity: Some(score) }),
+            }))
+        } else {
+            Ok(Poll::Pending)
+        }
+    }
 }

crates/milli/src/update/upgrade/mod.rs

@@ -41,6 +41,7 @@ const UPGRADE_FUNCTIONS: &[&dyn UpgradeIndex] = &[
     &ToTargetNoOp { target: (1, 21, 0) },
     &ToTargetNoOp { target: (1, 22, 0) },
     &ToTargetNoOp { target: (1, 23, 0) },
+    &ToTargetNoOp { target: (1, 24, 0) },
     // This is the last upgrade function, it will be called when the index is up to date.
     // any other upgrade function should be added before this one.
     &ToCurrentNoOp {},
@@ -75,6 +76,7 @@ const fn start(from: (u32, u32, u32)) -> Option<usize> {
         (1, 21, _) => function_index!(11),
         (1, 22, _) => function_index!(12),
         (1, 23, _) => function_index!(13),
+        (1, 24, _) => function_index!(14),
         // We deliberately don't add a placeholder with (VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH) here to force manually
         // considering dumpless upgrade.
         (_major, _minor, _patch) => return None,

crates/milli/src/vector/store.rs

@@ -8,6 +8,7 @@ use serde::{Deserialize, Serialize};
 
 use crate::progress::Progress;
 use crate::vector::Embeddings;
+use crate::TimeBudget;
 
 const HANNOY_EF_CONSTRUCTION: usize = 125;
 const HANNOY_M: usize = 16;
@@ -591,6 +592,7 @@ impl VectorStore {
         vector: &[f32],
         limit: usize,
         filter: Option<&RoaringBitmap>,
+        time_budget: &TimeBudget,
     ) -> crate::Result<Vec<(ItemId, f32)>> {
         if self.backend == VectorStoreBackend::Arroy {
             if self.quantized {
@@ -601,11 +603,25 @@ impl VectorStore {
                     .map_err(Into::into)
             }
         } else if self.quantized {
-            self._hannoy_nns_by_vector(rtxn, self._hannoy_quantized_db(), vector, limit, filter)
+            self._hannoy_nns_by_vector(
-                .map_err(Into::into)
+                rtxn,
+                self._hannoy_quantized_db(),
+                vector,
+                limit,
+                filter,
+                time_budget,
+            )
+            .map_err(Into::into)
         } else {
-            self._hannoy_nns_by_vector(rtxn, self._hannoy_angular_db(), vector, limit, filter)
+            self._hannoy_nns_by_vector(
-                .map_err(Into::into)
+                rtxn,
+                self._hannoy_angular_db(),
+                vector,
+                limit,
+                filter,
+                time_budget,
+            )
+            .map_err(Into::into)
         }
     }
     pub fn item_vectors(&self, rtxn: &RoTxn, item_id: u32) -> crate::Result<Vec<Vec<f32>>> {
@@ -1000,6 +1016,7 @@ impl VectorStore {
         vector: &[f32],
         limit: usize,
         filter: Option<&RoaringBitmap>,
+        time_budget: &TimeBudget,
     ) -> Result<Vec<(ItemId, f32)>, hannoy::Error> {
         let mut results = Vec::new();
 
@@ -1011,7 +1028,10 @@ impl VectorStore {
                 searcher.candidates(filter);
             }
 
-            results.append(&mut searcher.by_vector(rtxn, vector)?);
+            let (res, _degraded) =
+                &mut searcher
+                    .by_vector_with_cancellation(rtxn, vector, || time_budget.exceeded())?;
+            results.append(res);
         }
 
         results.sort_unstable_by_key(|(_, distance)| OrderedFloat(*distance));

documentation/prototypes.md

@@ -20,14 +20,16 @@ These make us iterate fast before stabilizing it for the current release.
 
 ### Release steps
 
-The prototype name must follow this convention: `prototype-X-Y` where
+The prototype name must follow this convention: `prototype-v<version>.<name>-<number>` where
-- `X` is the feature name formatted in `kebab-case`. It should not end with a single number.
+- `version` is the version of Meilisearch on which the prototype is based.
+- `name` is the feature name formatted in `kebab-case`. It should not end with a single number.
 - `Y` is the version of the prototype, starting from `0`.
 
-✅ Example: `prototype-auto-resize-0`. </br>
+✅ Example: `prototype-v1.23.0.search-personalization-0`. </br>
-❌ Bad example: `auto-resize-0`: lacks the `prototype` prefix. </br>
+❌ Bad example: `prototype-search-personalization-0`: version is missing.</br>
-❌ Bad example: `prototype-auto-resize`: lacks the version suffix. </br>
+❌ Bad example: `v1.23.0.auto-resize-0`: lacks the `prototype` prefix. </br>
-❌ Bad example: `prototype-auto-resize-0-0`: feature name ends with a single number.
+❌ Bad example: `prototype-v1.23.0.auto-resize`: lacks the version suffix. </br>
+❌ Bad example: `prototype-v1.23.0.auto-resize-0-0`: feature name ends with a single number.
 
 Steps to create a prototype: