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Re: Why volatile may make sense for parallel code today.

From "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups comp.lang.c++
Subject Re: Why volatile may make sense for parallel code today.
Date 2023-11-24 01:14 -0800
Organization A noiseless patient Spider
Message-ID <ujppgt$28srl$4@dont-email.me> (permalink)
References (1 earlier) <ujlrdv$1g6ej$1@dont-email.me> <ujm5n6$1hok4$1@redfloyd.dont-email.me> <ujmmia$1nmms$1@dont-email.me> <ujntc3$1p191$1@i2pn2.org> <ujnu49$1t7eu$1@raubtier-asyl.eternal-september.org>

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On 11/23/2023 8:20 AM, Bonita Montero wrote:
> Am 23.11.2023 um 17:07 schrieb Richard Damon:
> 
>> My understanding is that std:atomic needs to honor a read in the sense 
>> that it wlll get the most recent value that has happened "before" the 
>> read (as determined by memory order).
> 
> ... and the read is atomic - even if the trivial object is 1kB in size.

How is that read atomic with 1kb of data? On what arch?

> 
>> So, if nothing in the loop can establish a time order with respect to 
>> other threads, then it should be allowed for the compiler to optimize 
>> out the read. ...
> 
> An atomic doesn't cache repeatable reads. The order memory-consistency
> parameter is just for the ordering of other reads and writes.
> 
> 
> 

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Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-22 17:35 +0100
  Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-22 13:22 -0800
    Re: Why volatile may make sense for parallel code today. red floyd <no.spam.here@its.invalid> - 2023-11-22 16:17 -0800
      Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-22 21:05 -0800
        Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-22 21:06 -0800
          Re: Why volatile may make sense for parallel code today. Marcel Mueller <news.5.maazl@spamgourmet.org> - 2023-12-01 08:50 +0100
        Re: Why volatile may make sense for parallel code today. David Brown <david.brown@hesbynett.no> - 2023-11-23 10:02 +0100
          Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-23 10:35 +0100
          Re: Why volatile may make sense for parallel code today. scott@slp53.sl.home (Scott Lurndal) - 2023-11-23 19:55 +0000
            Re: Why volatile may make sense for parallel code today. David Brown <david.brown@hesbynett.no> - 2023-11-24 10:08 +0100
        Re: Why volatile may make sense for parallel code today. Richard Damon <richard@damon-family.org> - 2023-11-23 11:07 -0500
          Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-23 17:20 +0100
            Re: Why volatile may make sense for parallel code today. Richard Damon <richard@damon-family.org> - 2023-11-23 12:50 -0500
              Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-24 08:57 +0100
                Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-24 00:16 -0800
                Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-24 09:30 +0100
                Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-24 01:04 -0800
                Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-24 01:05 -0800
              Re: Why volatile may make sense for parallel code today. David Brown <david.brown@hesbynett.no> - 2023-11-24 10:23 +0100
            Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-23 22:05 -0800
              Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-23 22:53 -0800
              Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-24 08:53 +0100
                Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-24 01:06 -0800
                Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-24 10:10 +0100
            Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-24 01:14 -0800
              Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-24 15:32 -0800
    Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-23 08:08 +0100
      Re: Why volatile may make sense for parallel code today. Kaz Kylheku <864-117-4973@kylheku.com> - 2023-11-23 08:26 +0000
        Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-23 09:31 +0100
          Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-23 15:39 +0100
      Re: Why volatile may make sense for parallel code today. scott@slp53.sl.home (Scott Lurndal) - 2023-11-23 19:56 +0000
        Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-24 05:26 +0100
          Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-23 21:53 -0800
          Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-23 21:59 -0800
        Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-23 21:47 -0800
  Re: Why volatile may make sense for parallel code today. Kaz Kylheku <864-117-4973@kylheku.com> - 2023-11-23 20:32 +0000
    Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-24 05:27 +0100
      Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-23 21:55 -0800
      Re: Why volatile may make sense for parallel code today. David Brown <david.brown@hesbynett.no> - 2023-11-24 10:35 +0100
      Re: Why volatile may make sense for parallel code today. Kaz Kylheku <864-117-4973@kylheku.com> - 2023-11-24 18:27 +0000
        Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-24 15:37 -0800
        Re: Why volatile may make sense for parallel code today. Bonita Montero <Bonita.Montero@gmail.com> - 2023-11-25 13:11 +0100
          Re: Why volatile may make sense for parallel code today. "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-25 14:46 -0800

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