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Re: Patch to make string-append on win32 100 times faster

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August 21, 2010 04:46
Re: Patch to make string-append on win32 100 times faster
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On 21 August 2010 12:52, Wolfram Humann <> wrote:
> For a patched win32 perl I'll have to wait till Monday. What I can compare
> now is Strawberry (usemymalloc=n) to Cygwin (usemymalloc=y). This slightly
> golfed version

heh. :-)

> perl -MData::Dumper -E"sub mt{my $d=shift;$d>0?[mt($d-1),mt($d-1)]:int rand
> 100}; say length Dumper mt 18"
> 34576966
> needs approx. 6 seconds to print and 8 seconds to finish on both of these.

Interesting, how does that compare for you if you stick a


before the dump?

> No noticeable difference. With a touch of horror I have to report that the
> printed stringlengths are slightly non-deterministic from run to run...???


No worries there, the code does use rand() after all, so we expect to
see slightly different results from run to run (or the srand
initialization would be broken). Add a srand(1) or change the int rand
100 to a constant and it should produce repeatable results.

Anyway, thanks, i recall code like this taking unacceptably long (iow,
killed before it stopped) on Win2k with the XS version, and it taking
just-barely-acceptably long with the PP version (enabled by the Useqq
option as the XS code doesnt know how to do double-quoting.)

perl -Mre=debug -e "/just|another|perl|hacker/"

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