From 8dc3d68cbe676deb5e74d1b1b565f57fffaf107e Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 9 May 2021 19:33:24 -0400 Subject: [PATCH] Improve comments about USE_VALGRIND in pg_config_manual.h. These comments left the impression that USE_VALGRIND isn't really essential for valgrind testing. But that's wrong, as I learned the hard way today. Discussion: https://postgr.es/m/512778.1620588546@sss.pgh.pa.us --- src/include/pg_config_manual.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/src/include/pg_config_manual.h b/src/include/pg_config_manual.h index e28c9903823..42ee43f0aa7 100644 --- a/src/include/pg_config_manual.h +++ b/src/include/pg_config_manual.h @@ -279,12 +279,18 @@ * enables detection of buffer accesses that take place without holding a * buffer pin (or without holding a buffer lock in the case of index access * methods that superimpose their own custom client requests on top of the - * generic bufmgr.c requests). See also src/tools/valgrind.supp. + * generic bufmgr.c requests). * * "make installcheck" is significantly slower under Valgrind. The client * requests fall in hot code paths, so USE_VALGRIND slows execution by a few * percentage points even when not run under Valgrind. * + * Do not try to test the server under Valgrind without having built the + * server with USE_VALGRIND; else you will get false positives from sinval + * messaging (see comments in AddCatcacheInvalidationMessage). It's also + * important to use the suppression file src/tools/valgrind.supp to + * exclude other known false positives. + * * You should normally use MEMORY_CONTEXT_CHECKING with USE_VALGRIND; * instrumentation of repalloc() is inferior without it. */ -- 2.39.5