From 0e8e1f961ced96d0a910e421cc2531c5429f63ee Mon Sep 17 00:00:00 2001
From: Jay Deng <jayd0104@gmail.com>
Date: Tue, 25 Jul 2023 09:33:29 -0700
Subject: [PATCH] Create separate SourceLookup instance per segment slice in
 SignificantTextAggregatorFactory

Signed-off-by: Jay Deng <jayd0104@gmail.com>
---
 CHANGELOG.md                                                | 1 +
 .../bucket/terms/SignificantTextAggregatorFactory.java      | 6 +++---
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4bc645ed1bd6a..e875900aa222a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -93,6 +93,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Change InternalSignificantTerms to sum shard-level superset counts only in final reduce ([#8735](https://github.com/opensearch-project/OpenSearch/pull/8735))
 - Exclude 'benchmarks' from codecov report ([#8805](https://github.com/opensearch-project/OpenSearch/pull/8805))
 - [Refactor] MediaTypeParser to MediaTypeParserRegistry ([#8636](https://github.com/opensearch-project/OpenSearch/pull/8636))
+- Create separate SourceLookup instance per segment slice in SignificantTextAggregatorFactory ([#8807](https://github.com/opensearch-project/OpenSearch/pull/8807))
 
 ### Deprecated
 
diff --git a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/SignificantTextAggregatorFactory.java b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/SignificantTextAggregatorFactory.java
index e5cc3f9dbaabd..7f5804c8b9561 100644
--- a/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/SignificantTextAggregatorFactory.java
+++ b/server/src/main/java/org/opensearch/search/aggregations/bucket/terms/SignificantTextAggregatorFactory.java
@@ -148,7 +148,6 @@ protected Aggregator createInternal(
             : includeExclude.convertToStringFilter(DocValueFormat.RAW, maxRegexLength);
 
         MapStringTermsAggregator.CollectorSource collectorSource = new SignificantTextCollectorSource(
-            queryShardContext.lookup().source(),
             queryShardContext.bigArrays(),
             fieldType,
             sourceFieldNames,
@@ -186,13 +185,14 @@ private static class SignificantTextCollectorSource implements MapStringTermsAgg
         private ObjectArray<DuplicateByteSequenceSpotter> dupSequenceSpotters;
 
         SignificantTextCollectorSource(
-            SourceLookup sourceLookup,
             BigArrays bigArrays,
             MappedFieldType fieldType,
             String[] sourceFieldNames,
             boolean filterDuplicateText
         ) {
-            this.sourceLookup = sourceLookup;
+            // Create a new SourceLookup instance per aggregator instead of use the shared one from SearchLookup. This is fine because it
+            // will only be accessed by this Aggregator instance and not anywhere else.
+            this.sourceLookup = new SourceLookup();
             this.bigArrays = bigArrays;
             this.fieldType = fieldType;
             this.sourceFieldNames = sourceFieldNames;