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From: Bonita Montero <Bonita.Montero@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: signalling a condvar from inside vs. signalling a condvar von
 outside
Date: Sun, 13 Apr 2025 22:08:15 +0200
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Am 13.04.2025 um 21:32 schrieb Chris M. Thomasson:
> On 4/13/2025 8:38 AM, Bonita Montero wrote:
>> Am 12.04.2025 um 21:33 schrieb Chris M. Thomasson:
>>
>>> There is a scalability problem wrt signalling inside the critical 
>>> section. Does your convdar impl use wait morphing?
>>
>> There's no scalability problem with that since the kernel call to
>> release a thread happens only when the mutex is accessible *and*
>> the cv is signalled.
>>
>>
> 
> No. ...

The numer of context-switches my code shows say that there's only
one context-switchz per wait.

>When you signal a condvar while holding the lock it means that  waiters can wake and just instantly wait on the lock. This is why wait 
> morphing was created. It helps, but only so much...


idiot.