From a5a31f2754bf69a81fdc48769c1ee950317a2cf0 Mon Sep 17 00:00:00 2001 From: Nathan Bossart Date: Thu, 3 Apr 2025 13:20:28 -0500 Subject: [PATCH v12n6 1/4] Skip second WriteToc() call for custom-format dumps without data. Presently, "pg_dump --format=custom" calls WriteToc() twice. The second call updates the data offset information, which allegedly makes parallel pg_restore significantly faster. However, if we're not dumping any data, there are no data offsets to update, so we can skip this step. Reviewed-by: Jeff Davis Discussion: https://postgr.es/m/Z9c1rbzZegYQTOQE%40nathan --- src/bin/pg_dump/pg_backup_custom.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/src/bin/pg_dump/pg_backup_custom.c b/src/bin/pg_dump/pg_backup_custom.c index e44b887eb29..f7c3af56304 100644 --- a/src/bin/pg_dump/pg_backup_custom.c +++ b/src/bin/pg_dump/pg_backup_custom.c @@ -755,9 +755,11 @@ _CloseArchive(ArchiveHandle *AH) * If possible, re-write the TOC in order to update the data offset * information. This is not essential, as pg_restore can cope in most * cases without it; but it can make pg_restore significantly faster - * in some situations (especially parallel restore). + * in some situations (especially parallel restore). We can skip this + * step if we're not dumping any data; there are no offsets to update + * in that case. */ - if (ctx->hasSeek && + if (ctx->hasSeek && AH->public.dopt->dumpData && fseeko(AH->FH, tpos, SEEK_SET) == 0) WriteToc(AH); } -- 2.39.5 (Apple Git-154)