From 13980069b5e86cadcde35b7ab110ccf2e962abc2 Mon Sep 17 00:00:00 2001
From: Antonin Houska <ah@cybertec.at>
Date: Mon, 16 Mar 2026 13:53:30 +0100
Subject: [PATCH] Fix a few problems in index build progress reporting.

First, index_build() should not update the progress when being driven by
REPACK, because the progress reporting infractructure cannot handle status of
two commands at the same time. So far, REPACK with the CONCURRENTLY option
neglected this problem altogether, but even the existing REPACK wasn't
consistent enough: even if the 'progress' variable in repack_index() was
false, it didn't pass the value to index_build().

Second, REPACK (CONCURRENTLY) should not set PROGRESS_REPACK_PHASE to
PROGRESS_REPACK_PHASE_FINAL_CLEANUP in rebuild_relation() because it calls
finish_heap_swap() anyway (via rebuild_relation_finish_concurrent()), which
does the same thing.
---
 src/backend/bootstrap/bootstrap.c |  2 +-
 src/backend/catalog/heap.c        |  3 ++-
 src/backend/catalog/index.c       | 22 ++++++++++++++++++----
 src/backend/catalog/toasting.c    |  3 ++-
 src/backend/commands/cluster.c    |  7 ++++---
 src/backend/commands/indexcmds.c  |  1 +
 src/include/catalog/index.h       |  4 +++-
 7 files changed, 31 insertions(+), 11 deletions(-)

diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index 17118f2fe76..cb06c52c1d4 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -1180,7 +1180,7 @@ build_indices(void)
 		heap = table_open(ILHead->il_heap, NoLock);
 		ind = index_open(ILHead->il_ind, NoLock);
 
-		index_build(heap, ind, ILHead->il_info, false, false);
+		index_build(heap, ind, ILHead->il_info, false, false, false);
 
 		index_close(ind, NoLock);
 		table_close(heap, NoLock);
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 5748aa9a1a9..ae6b7cda3dd 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -3570,7 +3570,8 @@ RelationTruncateIndexes(Relation heapRelation)
 
 		/* Initialize the index and rebuild */
 		/* Note: we do not need to re-establish pkey setting */
-		index_build(heapRelation, currentIndex, indexInfo, true, false);
+		index_build(heapRelation, currentIndex, indexInfo, true, false,
+					true);
 
 		/* We're done with this index */
 		index_close(currentIndex, NoLock);
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index b1e05d56a1e..89aad2f7b77 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -714,6 +714,9 @@ UpdateIndexRelation(Oid indexoid,
  *			already exists.
  *		INDEX_CREATE_PARTITIONED:
  *			create a partitioned index (table must be partitioned)
+ *		INDEX_CREATE_REPORT_PROGRESS:
+ *			update the backend's progress information during index build.
+
  * constr_flags: flags passed to index_constraint_create
  *		(only if INDEX_CREATE_ADD_CONSTRAINT is set)
  * allow_system_table_mods: allow table to be a system catalog
@@ -759,6 +762,7 @@ index_create(Relation heapRelation,
 	bool		invalid = (flags & INDEX_CREATE_INVALID) != 0;
 	bool		concurrent = (flags & INDEX_CREATE_CONCURRENT) != 0;
 	bool		partitioned = (flags & INDEX_CREATE_PARTITIONED) != 0;
+	bool		progress = (flags & INDEX_CREATE_REPORT_PROGRESS) != 0;
 	char		relkind;
 	TransactionId relfrozenxid;
 	MultiXactId relminmxid;
@@ -1275,7 +1279,8 @@ index_create(Relation heapRelation,
 	}
 	else
 	{
-		index_build(heapRelation, indexRelation, indexInfo, false, true);
+		index_build(heapRelation, indexRelation, indexInfo, false, true,
+					progress);
 	}
 
 	/*
@@ -1454,6 +1459,12 @@ index_create_copy(Relation heapRelation, Oid oldIndexId, Oid tablespaceOid,
 		stattargets[i].isnull = isnull;
 	}
 
+	/*
+	 * Note: The current callers do not need INDEX_CREATE_REPORT_PROGRESS. If
+	 * 'concurrently' is true, there is no build at all. Otherwise the index
+	 * build is a sub-command of REPACK. The current infrastructure does not
+	 * allow two commands to report their progress at the same time.
+	 */
 	if (concurrently)
 		flags = INDEX_CREATE_SKIP_BUILD | INDEX_CREATE_CONCURRENT;
 
@@ -1544,7 +1555,7 @@ index_concurrently_build(Oid heapRelationId,
 	indexInfo->ii_BrokenHotChain = false;
 
 	/* Now build the index */
-	index_build(heapRel, indexRelation, indexInfo, false, true);
+	index_build(heapRel, indexRelation, indexInfo, false, true, true);
 
 	/* Roll back any GUC changes executed by index functions */
 	AtEOXact_GUC(false, save_nestlevel);
@@ -3017,6 +3028,7 @@ index_update_stats(Relation rel,
  *
  * isreindex indicates we are recreating a previously-existing index.
  * parallel indicates if parallelism may be useful.
+ * progress indicates if the backend should update its progress info.
  *
  * Note: before Postgres 8.2, the passed-in heap and index Relations
  * were automatically closed by this routine.  This is no longer the case.
@@ -3027,7 +3039,8 @@ index_build(Relation heapRelation,
 			Relation indexRelation,
 			IndexInfo *indexInfo,
 			bool isreindex,
-			bool parallel)
+			bool parallel,
+			bool progress)
 {
 	IndexBuildResult *stats;
 	Oid			save_userid;
@@ -3078,6 +3091,7 @@ index_build(Relation heapRelation,
 	RestrictSearchPath();
 
 	/* Set up initial progress report status */
+	if (progress)
 	{
 		const int	progress_index[] = {
 			PROGRESS_CREATEIDX_PHASE,
@@ -3835,7 +3849,7 @@ reindex_index(const ReindexStmt *stmt, Oid indexId,
 
 	/* Initialize the index and rebuild */
 	/* Note: we do not need to re-establish pkey setting */
-	index_build(heapRelation, iRel, indexInfo, true, true);
+	index_build(heapRelation, iRel, indexInfo, true, true, progress);
 
 	/* Re-allow use of target index */
 	ResetReindexProcessing();
diff --git a/src/backend/catalog/toasting.c b/src/backend/catalog/toasting.c
index 078a1cf5127..73c41360ae9 100644
--- a/src/backend/catalog/toasting.c
+++ b/src/backend/catalog/toasting.c
@@ -331,7 +331,8 @@ create_toast_table(Relation rel, Oid toastOid, Oid toastIndexOid,
 				 BTREE_AM_OID,
 				 rel->rd_rel->reltablespace,
 				 collationIds, opclassIds, NULL, coloptions, NULL, (Datum) 0,
-				 INDEX_CREATE_IS_PRIMARY, 0, true, true, NULL);
+				 INDEX_CREATE_IS_PRIMARY | INDEX_CREATE_REPORT_PROGRESS, 0,
+				 true, true, NULL);
 
 	table_close(toast_rel, NoLock);
 
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index fe419ef808e..9aaa8e95389 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -1162,9 +1162,6 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose,
 
 		rebuild_relation_finish_concurrent(NewHeap, OldHeap, ident_idx,
 										   frozenXid, cutoffMulti);
-
-		pgstat_progress_update_param(PROGRESS_REPACK_PHASE,
-									 PROGRESS_REPACK_PHASE_FINAL_CLEANUP);
 	}
 	else
 	{
@@ -3505,6 +3502,10 @@ rebuild_relation_finish_concurrent(Relation NewHeap, Relation OldHeap,
 	relpersistence = OldHeap->rd_rel->relpersistence;
 	is_system_catalog = IsSystemRelation(OldHeap);
 
+	/*
+	 * finish_heap_swap() sets the phase too, but here we need some swapping
+	 * in advance.
+	 */
 	pgstat_progress_update_param(PROGRESS_REPACK_PHASE,
 								 PROGRESS_REPACK_PHASE_SWAP_REL_FILES);
 
diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c
index 34209bd1393..ad5c1238e09 100644
--- a/src/backend/commands/indexcmds.c
+++ b/src/backend/commands/indexcmds.c
@@ -1230,6 +1230,7 @@ DefineIndex(ParseState *pstate,
 		flags |= INDEX_CREATE_PARTITIONED;
 	if (stmt->primary)
 		flags |= INDEX_CREATE_IS_PRIMARY;
+	flags |= INDEX_CREATE_REPORT_PROGRESS;
 
 	/*
 	 * If the table is partitioned, and recursion was declined but partitions
diff --git a/src/include/catalog/index.h b/src/include/catalog/index.h
index 3426087b445..3778e9b7f07 100644
--- a/src/include/catalog/index.h
+++ b/src/include/catalog/index.h
@@ -65,6 +65,7 @@ extern void index_check_primary_key(Relation heapRel,
 #define	INDEX_CREATE_IF_NOT_EXISTS			(1 << 4)
 #define	INDEX_CREATE_PARTITIONED			(1 << 5)
 #define INDEX_CREATE_INVALID				(1 << 6)
+#define INDEX_CREATE_REPORT_PROGRESS		(1 << 7)
 
 extern Oid	index_create(Relation heapRelation,
 						 const char *indexRelationName,
@@ -146,7 +147,8 @@ extern void index_build(Relation heapRelation,
 						Relation indexRelation,
 						IndexInfo *indexInfo,
 						bool isreindex,
-						bool parallel);
+						bool parallel,
+						bool progress);
 
 extern void validate_index(Oid heapId, Oid indexId, Snapshot snapshot);
 
-- 
2.47.3

