Merge pull request #5565 from meilisearch/fix-0-batched-task

Fix 0 batched task

crates/index-scheduler/src/lib.rs

@@ -383,6 +383,11 @@ impl IndexScheduler {
     /// This function will execute in a different thread and must be called
     /// only once per index scheduler.
     fn run(&self) {
+        // If the number of batched tasks is 0, we don't need to run the scheduler at all.
+        // It will never be able to process any tasks.
+        if self.scheduler.max_number_of_batched_tasks == 0 {
+            return;
+        }
         let run = self.private_clone();
         std::thread::Builder::new()
             .name(String::from("scheduler"))

crates/index-scheduler/src/scheduler/snapshots/test.rs/test_scheduler_doesnt_run_with_zero_batched_tasks/after_restart.snap

@@ -0,0 +1,63 @@
+---
+source: crates/index-scheduler/src/scheduler/test.rs
+---
+### Autobatching Enabled = true
+### Processing batch None:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, batch_uid: 0, status: succeeded, details: { primary_key: None }, kind: IndexCreation { index_uid: "doggos", primary_key: None }}
+----------------------------------------------------------------------
+### Status:
+enqueued []
+succeeded [0,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+doggos: { number_of_documents: 0, field_distribution: {} }
+
+----------------------------------------------------------------------
+### Canceled By:
+
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### All Batches:
+0 {uid: 0, details: {}, stats: {"totalNbTasks":1,"status":{"succeeded":1},"types":{"indexCreation":1},"indexUids":{"doggos":1}}, stop reason: "task with id 0 of type `indexCreation` cannot be batched", }
+----------------------------------------------------------------------
+### Batch to tasks mapping:
+0 [0,]
+----------------------------------------------------------------------
+### Batches Status:
+succeeded [0,]
+----------------------------------------------------------------------
+### Batches Kind:
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Batches Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Batches Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Batches Started At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Batches Finished At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------

crates/index-scheduler/src/scheduler/snapshots/test.rs/test_scheduler_doesnt_run_with_zero_batched_tasks/registered_task.snap

@@ -0,0 +1,51 @@
+---
+source: crates/index-scheduler/src/scheduler/test.rs
+---
+### Autobatching Enabled = true
+### Processing batch None:
+[]
+----------------------------------------------------------------------
+### All Tasks:
+0 {uid: 0, status: enqueued, details: { primary_key: None }, kind: IndexCreation { index_uid: "doggos", primary_key: None }}
+----------------------------------------------------------------------
+### Status:
+enqueued [0,]
+----------------------------------------------------------------------
+### Kind:
+"indexCreation" [0,]
+----------------------------------------------------------------------
+### Index Tasks:
+doggos [0,]
+----------------------------------------------------------------------
+### Index Mapper:
+
+----------------------------------------------------------------------
+### Canceled By:
+
+----------------------------------------------------------------------
+### Enqueued At:
+[timestamp] [0,]
+----------------------------------------------------------------------
+### Started At:
+----------------------------------------------------------------------
+### Finished At:
+----------------------------------------------------------------------
+### All Batches:
+----------------------------------------------------------------------
+### Batch to tasks mapping:
+----------------------------------------------------------------------
+### Batches Status:
+----------------------------------------------------------------------
+### Batches Kind:
+----------------------------------------------------------------------
+### Batches Index Tasks:
+----------------------------------------------------------------------
+### Batches Enqueued At:
+----------------------------------------------------------------------
+### Batches Started At:
+----------------------------------------------------------------------
+### Batches Finished At:
+----------------------------------------------------------------------
+### File Store:
+
+----------------------------------------------------------------------

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

@@ -929,3 +929,30 @@ fn create_and_list_index() {
     ]
     "###);
 }
+
+#[test]
+fn test_scheduler_doesnt_run_with_zero_batched_tasks() {
+    let (index_scheduler, mut handle) = IndexScheduler::test_with_custom_config(vec![], |config| {
+        config.max_number_of_batched_tasks = 0;
+        None
+    });
+
+    handle.scheduler_is_down();
+
+    // Register a task
+    index_scheduler
+        .register(
+            KindWithContent::IndexCreation { index_uid: S("doggos"), primary_key: None },
+            None,
+            false,
+        )
+        .unwrap();
+    snapshot!(snapshot_index_scheduler(&index_scheduler), name: "registered_task");
+
+    handle.scheduler_is_down();
+
+    // If we restart the scheduler, it should run properly.
+    let (index_scheduler, mut handle) = handle.restart(index_scheduler, true, vec![], |_| None);
+    handle.advance_n_successful_batches(1);
+    snapshot!(snapshot_index_scheduler(&index_scheduler), name: "after_restart");
+}

crates/index-scheduler/src/test_utils.rs

@@ -119,6 +119,9 @@ impl IndexScheduler {
             (versioning::VERSION_MAJOR, versioning::VERSION_MINOR, versioning::VERSION_PATCH)
         });
 
+        // If the number of batched tasks is 0, the scheduler will not run and we can't do the init check.
+        let skip_init = options.max_number_of_batched_tasks == 0;
+
         std::fs::create_dir_all(&options.auth_path).unwrap();
         let auth_env = open_auth_store_env(&options.auth_path).unwrap();
         let index_scheduler =
@@ -127,7 +130,11 @@ impl IndexScheduler {
         // To be 100% consistent between all test we're going to start the scheduler right now
         // and ensure it's in the expected starting state.
         let breakpoint = match receiver.recv_timeout(std::time::Duration::from_secs(10)) {
+            Ok(b) if skip_init => {
+                panic!("The scheduler was not supposed to start, but it did: {b:?}.")
+            }
             Ok(b) => b,
+            Err(_) if skip_init => (Init, false),
             Err(RecvTimeoutError::Timeout) => {
                 panic!("The scheduler seems to be waiting for a new task while your test is waiting for a breakpoint.")
             }