On Thu, Nov 30, 2023 at 07:56:27PM -0800, Andres Freund wrote:
> On 2023-11-30 21:18:15 -0600, Nathan Bossart wrote:
>> Some rudimentary tests show a >40% speedup with this patch on x86_64.
>
> On bigger machines, with contention, the wins are likely much higher. I see
> two orders of magnitude higher throughput in a test program that I had around,
> on a two socket cascade lake machine. Of course it's also much less
> powerfull...
Nice. Thanks for trying it out.
One thing on my mind is whether we should bother with the inline assembly
versions. It looks like gcc has had __atomic since 4.7.0 (2012), so I'm
not sure we gain much from them. OTOH they are pretty simple and seem
unlikely to cause too much trouble.
--
Nathan Bossart
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