On Feb 6 21:39, Magnus Holmgren wrote: > Corinna Vinschen <corinna-cygwin <at> cygwin.com> 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 -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader cygwin AT cygwin DOT com Red Hat -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple