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Re: [ANNOUNCEMENT] Updated: cygwin-1.7.10-1

On Feb  6 21:39, Magnus Holmgren wrote:
> Corinna Vinschen <corinna-cygwin <at>> writes:
> > - Improve fork/exec performance on 64 bit systems.
> If fork/exec became faster, something else has slowed down noticeably on my
> 64-bit Vista system. Using a fairly fork-heavy build script as the benchmark
> (and running it when nothing needs to be re-built), 1.7.10 is about 25% slower.
> Switching to cygwin1.dll 1.7.9 speeds things up again (and I only changed the
> DLL; it seemed to work fine for this test at least).
> The "while [ 1 ]; do date; done | uniq -c" loop is about 15% faster with 1.7.10
> though.

I can't reproduce this.  I tested with `make clean; make' in a tcsh
build tree, and the 1.7.9 build is always slower, about 20%.

> Lines like these stand out in a quick look in the strace log (about 75 MB):
> 1172898 1173730 [main] sh 1484 child_copy: dll bss - hp 0xEC low 0x611FC000,
> high 0x61230770, res 1
> Every 4-5 print of "child_copy: dll bss" starts with a big number like that
> (values in the 50000-100000 range are more common). Don't know if this is
> relevant...

That hasn't changed between 1.7.9 and 1.7.0.  We always have to copy
parent data to the child in fork.  Sigh.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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