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Re: advantage using multiple cpus
On Mon, May 07, 2007 at 07:20:18PM +0200, olaf.selke@xxxxxxxxxxxx wrote 0.8K bytes in 18 lines about:
: I'm running tor on a dual Xeon Linux box having the numcpus param set to
: the value of four. Bios reports two Xeon cpus with hyperthreading to the
: Linux kernel 2.6.18 as four processors. Nevertheless throughput appears
: to be limited by the cpu running the main thread doing nearly all the work:
You want the NumCPU to be set to 2. You have two physical cpus.
The way the linux kernel interprets the HT part looks like 2
more cpus, but in reality, the kernel scheduler knows you only have 2, not 4.
I suggest setting it to 2 and seeing if performance improves for
you. Hopefully, empirical research on a sample size of one
system avoids a lengthy thread about HT vs. real cpus.