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From: "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: Futexes ain't fast
Date: Mon, 2 Sep 2024 11:56:24 -0700
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On 8/30/2024 5:36 PM, jseigh wrote:
> On 8/30/24 15:45, Chris M. Thomasson wrote:
>> On 8/30/2024 6:31 AM, jseigh wrote:
> ...
>>>
>>> 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.
>>
>> 100% agreed. Eventcounts are in the mix as well.
>>
> 
> You might take a look at folly's eventcount.  It (I think) only calls
> futex wake if there are waiters, and only calls futex_wait if the
> eventcount hasn't been incremented.  I did my own C version since I'm
> working in C for now.

I need to look at it. Have been really busy lately. I think you said 
that eventcounts can be a little "too" lock-free? ;^)