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Groups > comp.lang.c++ > #117934
| 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 | 2023-11-23 22:53 -0800 |
| Organization | A noiseless patient Spider |
| Message-ID | <ujph95$27qmb$1@dont-email.me> (permalink) |
| References | (2 earlier) <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> <ujpefk$27eto$2@dont-email.me> |
On 11/23/2023 10:05 PM, Chris M. Thomasson wrote: > 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. > > humm.. Say, the read is from a word in memory. Define your trivial > object, POD, l2 cache line sized, and aligned on a l2 cache line > boundary? Are you refering to how certain arch works? How many words in your cache lines, say l2? > >> >>> 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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