Date: Tue, 30 Sep 2025 16:15:07 GMT From: Mateusz Guzik <mjg@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 2bdc89535a88 - main - amd64: bump sleepq hash size to 2048 Message-ID: <202509301615.58UGF7CO043328@gitrepo.freebsd.org>
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The branch main has been updated by mjg: URL: https://cgit.FreeBSD.org/src/commit/?id=2bdc89535a8837347bb3b523715bba021dea4418 commit 2bdc89535a8837347bb3b523715bba021dea4418 Author: Mateusz Guzik <mjg@FreeBSD.org> AuthorDate: 2025-09-30 14:06:48 +0000 Commit: Mateusz Guzik <mjg@FreeBSD.org> CommitDate: 2025-09-30 16:14:55 +0000 amd64: bump sleepq hash size to 2048 This is the most contended lock type during the first hour of -j 104 poudriere. Drops significantly with the change. Note there are suspicous acquires which most likely don't need to happen, artificially exacerbating tehe problem.. --- sys/amd64/include/param.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/sys/amd64/include/param.h b/sys/amd64/include/param.h index 5a9c3162e14c..0654bb9de790 100644 --- a/sys/amd64/include/param.h +++ b/sys/amd64/include/param.h @@ -150,6 +150,15 @@ (((va) >= kva_layout.dmap_low && (va) < kva_layout.dmap_high) || \ ((va) >= kva_layout.km_low && (va) < kva_layout.km_high)) -#define SC_TABLESIZE 1024 /* Must be power of 2. */ +/* + * Must be power of 2. + * + * Perhaps should be autosized on boot based on found ncpus. + */ +#if MAXCPU > 256 +#define SC_TABLESIZE 2048 +#else +#define SC_TABLESIZE 1024 +#endif #endif /* !_AMD64_INCLUDE_PARAM_H_ */
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