From b418054ee4bfb9b11c1172e3f3446fb448f844fc Mon Sep 17 00:00:00 2001
From: Louis Dureuil <louis@meilisearch.com>
Date: Wed, 15 Oct 2025 15:33:45 +0200
Subject: [PATCH] Change `bucket_sort` logic to pass the time budget and allow
 for retrieving non-blocking buckets

---
 crates/milli/src/search/new/bucket_sort.rs | 104 ++++++++++++---------
 1 file changed, 59 insertions(+), 45 deletions(-)

diff --git a/crates/milli/src/search/new/bucket_sort.rs b/crates/milli/src/search/new/bucket_sort.rs
index 50362b85b..72c0fed4e 100644
--- a/crates/milli/src/search/new/bucket_sort.rs
+++ b/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(
-            ctx,
-            logger,
-            &ranking_rule_universes[cur_ranking_rule_index],
-        )?
-        else {
-            back!();
-            continue;
+        let next_bucket = if time_budget.exceeded() {
+            match ranking_rules[cur_ranking_rule_index].non_blocking_next_bucket(
+                ctx,
+                logger,
+                &ranking_rule_universes[cur_ranking_rule_index],
+            )? {
+                std::task::Poll::Ready(bucket) => bucket,
+                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,
         )?;
     }