From 3462ca980c47d7bb6c93573e05f740eb3c89ded9 Mon Sep 17 00:00:00 2001 From: Manu Date: Mon, 21 Sep 2026 20:53:25 -0300 Subject: [PATCH v1 1/5] Fix blocks_done of an index build's heap scan on its first block heapam_scan_get_blocks_done() computes how many blocks a scan has done from the block it is on and the block it started at, allowing for a synchronized scan that wrapped around the end of the relation. When the current block is the start block, which only happens on the first block, it took the wrap-around branch and returned the number of blocks in the relation. So CREATE INDEX reported blocks_done = blocks_total as soon as the scan started, and then went back to 1 on the next block. Found with the PROGRESS_DEBUG tracing proposed in the same thread. Oversight in ab0dfc961b6. --- src/backend/access/heap/heapam_handler.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c index 6adb760b54f..499e426479c 100644 --- a/src/backend/access/heap/heapam_handler.c +++ b/src/backend/access/heap/heapam_handler.c @@ -1965,9 +1965,10 @@ heapam_scan_get_blocks_done(HeapScanDesc hscan) /* * Might have wrapped around the end of the relation, if startblock was - * not zero. + * not zero. The scan ends before coming back to startblock, so the + * current block is only startblock at the start, when no block is done. */ - if (hscan->rs_cblock > startblock) + if (hscan->rs_cblock >= startblock) blocks_done = hscan->rs_cblock - startblock; else { -- 2.55.0