From: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
To: "H.J. Lu" <hjl.tools@gmail.com>
Cc: 'GNU C Library' <libc-alpha@sourceware.org>
Subject: [PATCH v6 3/4] Reduce CAS in malloc spinlocks
Date: Mon, 15 Nov 2021 13:01:57 +0000 [thread overview]
Message-ID: <VE1PR08MB5599BE628E2CC1AE96787A0883989@VE1PR08MB5599.eurprd08.prod.outlook.com> (raw)
Hi,
A quick check shows that the atomic loads are always inserted before the first
CAS, and since these locks are mostly uncontended, this will actually hurt
performance on all targets. Also, it's not like we've ever had complaints about
the number of arenas we can create in malloc by having all CPUs create one at
exactly the same time...
So a change like this really need to show gains in malloc benchmarks.
Cheers,
Wilco
next reply other threads:[~2021-11-15 13:02 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-15 13:01 Wilco Dijkstra [this message]
-- strict thread matches above, loose matches on Subject: below --
2023-02-23 18:27 Wilco Dijkstra
2023-02-23 19:53 ` H.J. Lu
2023-02-23 20:07 ` DJ Delorie
2021-11-11 16:24 [PATCH v6 0/4] Optimize CAS [BZ #28537] H.J. Lu
2021-11-11 16:24 ` [PATCH v6 3/4] Reduce CAS in malloc spinlocks H.J. Lu
2023-02-23 5:48 ` DJ Delorie
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