From 0e82863c3750e0f8019709c31695a80cb21a37c3 Mon Sep 17 00:00:00 2001 From: Jingtang Zhang Date: Wed, 9 Sep 2026 11:38:03 +0800 Subject: [PATCH v2] Use maintenance_io_concurrency for parallel index builds. Mark parallel index build scans as maintenance work so their heap read streams use maintenance_io_concurrency instead of effective_io_concurrency. Apply this to B-tree, BRIN, and GIN parallel builds while preserving the existing sequential and batching behavior. --- src/backend/access/brin/brin.c | 2 +- src/backend/access/gin/gininsert.c | 2 +- src/backend/access/heap/heapam.c | 7 +++++-- src/backend/access/nbtree/nbtsort.c | 2 +- src/include/access/tableam.h | 3 +++ 5 files changed, 11 insertions(+), 5 deletions(-) diff --git a/src/backend/access/brin/brin.c b/src/backend/access/brin/brin.c index 5059da8dce7..b6f3f87d768 100644 --- a/src/backend/access/brin/brin.c +++ b/src/backend/access/brin/brin.c @@ -2845,7 +2845,7 @@ _brin_parallel_scan_and_build(BrinBuildState *state, scan = table_beginscan_parallel(heap, ParallelTableScanFromBrinShared(brinshared), - SO_NONE); + SO_MAINTENANCE); reltuples = table_index_build_scan(heap, index, indexInfo, true, true, brinbuildCallbackParallel, state, scan); diff --git a/src/backend/access/gin/gininsert.c b/src/backend/access/gin/gininsert.c index 37f689a2cac..07b5ca82167 100644 --- a/src/backend/access/gin/gininsert.c +++ b/src/backend/access/gin/gininsert.c @@ -2066,7 +2066,7 @@ _gin_parallel_scan_and_build(GinBuildState *state, scan = table_beginscan_parallel(heap, ParallelTableScanFromGinBuildShared(ginshared), - SO_NONE); + SO_MAINTENANCE); reltuples = table_index_build_scan(heap, index, indexInfo, true, progress, ginBuildCallbackParallel, state, scan); diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 72d6541734c..1bb5d6afa64 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -1281,6 +1281,10 @@ heap_beginscan(Relation relation, Snapshot snapshot, scan->rs_base.rs_flags & SO_TYPE_TIDRANGESCAN) { ReadStreamBlockNumberCB cb; + int stream_flags = READ_STREAM_SEQUENTIAL | READ_STREAM_USE_BATCHING; + + if (scan->rs_base.rs_flags & SO_MAINTENANCE) + stream_flags |= READ_STREAM_MAINTENANCE; if (scan->rs_base.rs_parallel) cb = heap_scan_stream_read_next_parallel; @@ -1294,8 +1298,7 @@ heap_beginscan(Relation relation, Snapshot snapshot, * - in the parallel case, only spinlocks and atomics are used * --- */ - scan->rs_read_stream = read_stream_begin_relation(READ_STREAM_SEQUENTIAL | - READ_STREAM_USE_BATCHING, + scan->rs_read_stream = read_stream_begin_relation(stream_flags, scan->rs_strategy, scan->rs_base.rs_rd, MAIN_FORKNUM, diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index 756dfa3dcf4..ff5ed01718c 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -1929,7 +1929,7 @@ _bt_parallel_scan_and_sort(BTSpool *btspool, BTSpool *btspool2, indexInfo->ii_Concurrent = btshared->isconcurrent; scan = table_beginscan_parallel(btspool->heap, ParallelTableScanFromBTShared(btshared), - SO_NONE); + SO_MAINTENANCE); reltuples = table_index_build_scan(btspool->heap, btspool->index, indexInfo, true, progress, _bt_build_callback, &buildstate, scan); diff --git a/src/include/access/tableam.h b/src/include/access/tableam.h index ff03a2b816f..31f49814433 100644 --- a/src/include/access/tableam.h +++ b/src/include/access/tableam.h @@ -72,6 +72,9 @@ typedef enum ScanOptions /* collect scan instrumentation */ SO_SCAN_INSTRUMENT = 1 << 11, + + /* use maintenance I/O concurrency */ + SO_MAINTENANCE = 1 << 12, } ScanOptions; /* -- 2.50.1 (Apple Git-155)