From 03a42c9652f8cc2c447840e39418b862c48fd41d Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Mon, 18 Nov 2024 11:44:11 +0900 Subject: [PATCH] Use pg_memory_is_all_zeros() in PageIsVerifiedExtended() Relying on pg_memory_is_all_zeros(), which would apply SIMD instructions when dealing with an aligned page, is proving to be at least three times faster than the original size_t-based comparisons when checking if a BLCKSZ page is full of zeros. Note that PageIsVerifiedExtended() is called each time a page is read from disk, and making it faster is a good thing. Author: Bertrand Drouvot Discussion: https://postgr.es/m/CAApHDvq7P-JgFhgtxUPqhavG-qSDVUhyWaEX9M8_MNorFEijZA@mail.gmail.com --- src/backend/storage/page/bufpage.c | 13 +------------ 1 file changed, 1 insertion(+), 12 deletions(-) diff --git a/src/backend/storage/page/bufpage.c b/src/backend/storage/page/bufpage.c index be6f1f62d29..aa264f61b9c 100644 --- a/src/backend/storage/page/bufpage.c +++ b/src/backend/storage/page/bufpage.c @@ -89,10 +89,8 @@ PageIsVerifiedExtended(Page page, BlockNumber blkno, int flags) { PageHeader p = (PageHeader) page; size_t *pagebytes; - int i; bool checksum_failure = false; bool header_sane = false; - bool all_zeroes = false; uint16 checksum = 0; /* @@ -126,18 +124,9 @@ PageIsVerifiedExtended(Page page, BlockNumber blkno, int flags) } /* Check all-zeroes case */ - all_zeroes = true; pagebytes = (size_t *) page; - for (i = 0; i < (BLCKSZ / sizeof(size_t)); i++) - { - if (pagebytes[i] != 0) - { - all_zeroes = false; - break; - } - } - if (all_zeroes) + if (pg_memory_is_all_zeros(pagebytes, BLCKSZ)) return true; /* -- 2.39.5