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From: jseigh <jseigh_es00@xemaps.com>
Newsgroups: comp.lang.c++
Subject: Re: Futexes ain't fast
Date: Fri, 30 Aug 2024 09:31:20 -0400
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On 8/28/2024 8:09 AM, Bonita Montero wrote:
> I tested the operating-system specific mutex (CRITICAL_SECTION Or
> pthread_mutext_t) against a futex and a std::mutex. I guessed std::mutex
> uses th operating system specific mutex internally, but the times varied
> so much across Windows and Linux that I gues that std::mutex used at
> least a differently parametrized operating system mutex or maybe even
> completely own code.
> This are the times and each line has a further contender:
> 

They don't have to be fast, they just have to allow correct synchronization
and allow performant fast paths.  Can the api be improved for the latter?
Certainly yes.  It is an awkward api to use.

Joe Seigh