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Re: setjmp, longjmp, parser state, threads

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On 28.07.2015 12:14, Ian Collins wrote:
> Morten W. Petersen wrote:
>>
>> Short snippets of code are good for a theoretical understanding of
>> something, but I think I understand threads well enough.  There is
>> a small memory cost, some cost of context switching and managing
>> threads, and working with large data sets can for example be slow
>> because it is outside of the CPU cache.
>>
>> Is there anything else to consider using threads?
>
> Synchronisation.
>
> If you have a number of threads building a shared data structure (an XML
> DOM for example), contention for locks on that structure can be a real
> performance killer, especially if it contains many small nodes.

Ah yes.  That can mostly be designed out as well I guess.

As for parsing, it looks like data structures that have been
completed can be marked as such using a simple flag, for example
that one of the pointers is pointing somewhere and is not NULL.

But again, at the synchronization point after the parsing, one
can just check that none of the threads are busy and then continue
and save that overhead.

-Morten

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setjmp, longjmp, parser state, threads "Morten W. Petersen" <morphex@gmail.com> - 2015-07-27 20:50 +0200
  Re: setjmp, longjmp, parser state, threads Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-07-28 00:22 +0100
    Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads] Jeff Higgins <jeff@invalid.invalid> - 2015-07-27 21:00 -0400
      Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state,   threads] Ian Collins <ian-news@hotmail.com> - 2015-07-28 13:57 +1200
        Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state,   threads] Jeff Higgins <jeff@invalid.invalid> - 2015-07-27 22:13 -0400
          Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state,     threads] Ian Collins <ian-news@hotmail.com> - 2015-07-28 17:12 +1200
            Re: OT - XML Parallel Parsing Jeff Higgins <jeff@invalid.invalid> - 2015-07-28 09:46 -0400
          Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads] "Morten W. Petersen" <morphex@gmail.com> - 2015-07-28 10:07 +0200
            Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads] raltbos@xs4all.nl (Richard Bos) - 2015-07-28 09:28 +0000
              Patents, was [Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads]] "Morten W. Petersen" <morphex@gmail.com> - 2015-07-28 11:41 +0200
                Re: Patents, was [Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads]] Stephen Sprunk <stephen@sprunk.org> - 2015-07-28 20:53 -0500
                Re: Patents, was [Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads]] "Morten W. Petersen" <morphex@gmail.com> - 2015-07-29 05:15 +0200
                Re: Patents, was [Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads]] Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2015-07-28 22:34 -0600
      Re: OT - XML Parallel Parsing, was [Re: setjmp, longjmp, parser state, threads] Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-07-28 03:06 +0100
    Re: setjmp, longjmp, parser state, threads "Morten W. Petersen" <morphex@gmail.com> - 2015-07-28 10:44 +0200
      Re: setjmp, longjmp, parser state, threads Ian Collins <ian-news@hotmail.com> - 2015-07-28 22:14 +1200
        Re: setjmp, longjmp, parser state, threads "Morten W. Petersen" <morphex@gmail.com> - 2015-07-28 15:17 +0200
      Re: setjmp, longjmp, parser state, threads Jeff Higgins <jeff@invalid.invalid> - 2015-07-28 08:35 -0400
      Re: setjmp, longjmp, parser state, threads James Kuyper <jameskuyper@verizon.net> - 2015-07-28 10:29 -0400
        Re: setjmp, longjmp, parser state, threads "Morten W. Petersen" <morphex@gmail.com> - 2015-07-28 16:39 +0200
  Re: setjmp, longjmp, parser state, threads jadill33@gmail.com - 2015-07-28 06:47 -0700
    Re: setjmp, longjmp, parser state, threads "Morten W. Petersen" <morphex@gmail.com> - 2015-07-28 16:56 +0200
      Re: setjmp, longjmp, parser state, threads Noob <root@127.0.0.1> - 2015-07-28 18:04 +0200
      Re: setjmp, longjmp, parser state, threads jadill33@gmail.com - 2015-07-28 10:53 -0700
        Re: setjmp, longjmp, parser state, threads "Morten W. Petersen" <morphex@gmail.com> - 2015-07-29 04:59 +0200
  Re: setjmp, longjmp, parser state, threads Bartc <bc@freeuk.com> - 2015-07-28 16:29 +0100

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