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Re: Example uses for read-modify-write operations?

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Am 04.09.19 um 14:14 schrieb already5chosen@yahoo.com:
> 
> I use it for simple parallel scheduler.
> Imagine N jobs or "work items" that can be done independently in arbitrary order. Then there is a pool of M working threads. You have a variable CNT that points to the next unassigned work items in the list. A main thread initializes a CNT, fires working threads and waits for their completion. Each working thread runs in a loop. At the beginning of the loop it does idx=Fetch-and-Add(CNT). If idx >= N then working thread exits otherwise it processes work item # idx and continues to the beginning of the loop. That's about all. Apart of multiple details.
> 

Thanks for giving a real-world example use of fetch-and-add.
From what I've read, fetch-and-add ist the most widely used of the RMW
operations.
Are there algorithms where one of the others occurs naturally (excluding
obvious rewrites of algorithms to use fetch-and-subtract intead of
fetch-and-add)?

Philipp

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Example uses for read-modify-write operations? Philipp Klaus Krause <pkk@spth.de> - 2019-09-04 11:20 +0200
  Re: Example uses for read-modify-write operations? Clifford Heath <no.spam@please.net> - 2019-09-04 20:44 +1000
    Re: Example uses for read-modify-write operations? Philipp Klaus Krause <pkk@spth.de> - 2019-09-04 13:26 +0200
      Re: Example uses for read-modify-write operations? Clifford Heath <no.spam@please.net> - 2019-09-04 22:13 +1000
        Re: Example uses for read-modify-write operations? Philipp Klaus Krause <pkk@spth.de> - 2019-09-04 14:33 +0200
      Re: Example uses for read-modify-write operations? already5chosen@yahoo.com - 2019-09-04 05:14 -0700
        Re: Example uses for read-modify-write operations? Philipp Klaus Krause <pkk@spth.de> - 2019-09-04 14:35 +0200
        Re: Example uses for read-modify-write operations? mark.bluemel@gmail.com - 2019-09-04 08:24 -0700
          Re: Example uses for read-modify-write operations? already5chosen@yahoo.com - 2019-09-04 08:37 -0700
          Re: Example uses for read-modify-write operations? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-09-04 17:10 +0100
  Re: Example uses for read-modify-write operations? Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-04 14:28 +0200

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