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Subject: Ring library optimization idea
Date: Sun, 20 Aug 2023 11:23:38 +0200
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Thread-Topic: Ring library optimization idea
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From: =?iso-8859-1?Q?Morten_Br=F8rup?= <mb@smartsharesystems.com>
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Cc: <honnappa.nagarahalli@arm.com>,
	<konstantin.v.ananyev@yandex.ru>
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Most of the fast path ring library functions access the two cache lines =
containing respectively the r->prod and r->cons structures.

Some of the fast path functions also have to fetch r->capacity and =
r->mask, which reside in another cache line.

What do you think about adding shadow variables of r->capacity and =
r->mask to the same cache line as r->prod, to improve ring library =
performance (by avoiding having to read a third cache line) when under =
CPU cache pressure?

-Morten