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Re: Signalling a condvar from inside and outside a locked mutex

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On 7/19/2024 9:43 PM, Chris M. Thomasson wrote:
> On 7/19/2024 12:05 PM, Scott Lurndal wrote:
>> "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> writes:
>>> On 7/19/2024 9:26 AM, Bonita Montero wrote:
>>> [...]
>>>>
>>>> outside: 19937
>>>> inside: 20030 100.471%
>>>>
>>>> Result: locking from inside and outside is as efficient with
>>>> Linux and  glibc, only half a percent more contextswitches
>>>> with locking from inside.
>>>
>>> Well, wait morphing should have something to do with it. ;^)
>>>
>>> Generally, signalling a condvar while the mutex is locked is not all
>>> that efficient...
>>
>>
>> One cannot draw any conclusions from that toy example.  It really
>> depends on what percentage of the time there is contention on the
>> mutex, how many waiters there are on average and the maturity of the
>> host thread scheduler.
> 
> Right. It can be tested under simulated and/or recorded real load. I 
> used to do this in some of my older server code.
> 

Turned out that some special algorithms were used during specific types 
of load, so to speak... This was a long time ago. Back when I won the 
the first part of the CoolThreads Contest. I got a T2000 SunFire server. 
Fun Times!

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Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-19 18:26 +0200
  Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-19 11:37 -0700
    Re: Signalling a condvar from inside and outside a locked mutex scott@slp53.sl.home (Scott Lurndal) - 2024-07-19 19:05 +0000
      Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-20 06:34 +0200
        Re: Signalling a condvar from inside and outside a locked mutex scott@slp53.sl.home (Scott Lurndal) - 2024-07-20 14:30 +0000
          Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-20 20:24 +0200
            Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-20 12:01 -0700
              Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-20 21:22 +0200
                Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-20 12:50 -0700
                Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-21 08:46 +0200
                Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-21 13:12 -0700
                Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-22 06:59 +0200
                Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-22 12:12 -0700
                Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-23 05:58 +0200
                Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-25 11:24 -0700
      Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-19 21:43 -0700
        Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-19 21:45 -0700
      Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-20 10:04 +0200
        Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-24 17:23 -0700
        Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-24 17:36 -0700
    Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-20 06:33 +0200
    Re: Signalling a condvar from inside and outside a locked mutex Marcel Mueller <news.5.maazl@spamgourmet.org> - 2024-07-21 14:14 +0200
      Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-21 14:19 +0200
        Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-21 13:08 -0700
      Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-21 13:07 -0700
        Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-22 07:00 +0200
        Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-22 07:17 +0200
          Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-22 12:13 -0700
            Re: Signalling a condvar from inside and outside a locked mutex Bonita Montero <Bonita.Montero@gmail.com> - 2024-07-23 10:39 +0200
              Re: Signalling a condvar from inside and outside a locked mutex "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-07-23 12:49 -0700

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