On 02/15/2011 11:29 AM, Dave Howorth wrote:
Jan Kara wrote:
time perl -e 'use threads; $T=12 ; foreach (1..$T) { $thr[$i++] = threads->create(sub { printf "I am thread %s\n", threads->tid(); foreach (1..9e6) { push(@a, sqrt(1234)/sin(1234)) } ; printf "thread %s finished.\n", threads->tid(); }); } foreach (0..$T-1) { $thr[$_]->join(); }'
what ugly perl :)
I started noticing this problem not with perl but with our CFD application compiled from C and FORTRAN. There I saw big performance differences between 2.6.34 and 2.6.37 on openSUSE 11.3. I saw the differences running on parallel and also in serial. Then I tried to find an example of this slowdown for others to test themselves on their machines, that's why I came out with this *simple* perl test, but I suppose any other language would do it. I could try a FORTRAN test and share my results. My last test some days ago was to update one of the openSUSE 11.3 nodes we have running to openSUSE 11.4 RC 1, and I saw no difference there on the perl test, so this looks promising again. I will have to run our own CFD application again on openSUSE 11.4 RC 1 and compare again. Richard -- Richard Ems mail: Richard.Ems@Cape-Horn-Eng.com Cape Horn Engineering S.L. C/ Dr. J.J. Dómine 1, 5º piso 46011 Valencia Tel : +34 96 3242923 / Fax 924 http://www.cape-horn-eng.com -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-kernel+help@opensuse.org