Re: IPC::Open2 multiple processes are all on the same CPU?

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Re^2: IPC::Open2 multiple processes are all on the same CPU? by nickswanjan (Initiate) on Oct 12, 2006 at 19:04 UTC
RHEL3, 2.4.21-40.ELsmp Perl v5.8.0 built for i386-linux-thread-multi I am executing the script from the shell, ./test.pl	[reply]
Re^3: IPC::Open2 multiple processes are all on the same CPU? by cephas (Pilgrim) on Oct 12, 2006 at 20:09 UTC
Strange. 2.4 kernels usually were notorious for bouncing processes from processor to processor, not keeping them stuck on one. You may want to try to check one of the kernel groups. Make sure to let them know exactly what kernel, and if there are 4 separate processors, or if it is hyperthreading (it is my understanding that multicore processors are treated slightly different, even though they'll show up as multiple logical processors in user space). If you want to get really hardcore you can set the processor affinity for those processes, letting them know which processor to run on. While that is normally 2.6 functionality, I believe it was backported into some of the Redhat kernels. I'd like to hear the final outcome of your investigations.	[reply]
Re^4: IPC::Open2 multiple processes are all on the same CPU? by nickswanjan (Initiate) on Oct 13, 2006 at 12:40 UTC
Do you think it might work better on a 2.6 kernel overall, even without the processor affinity? What is the function to set the processor affinity, or can I view what Perl might have set the affinity to?	[reply]