Messages in this thread | | | Date | Tue, 3 Jul 2001 11:51:39 -0700 | From | Mike Kravetz <> | Subject | Re: Strange thread behaviour on 8-way x86 machine |
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On Tue, Jul 03, 2001 at 12:25:12PM -0600, Sasha Pachev wrote: > Hi, > > I have observed a rather strange behaviour doing a multi-threaded CPU > benchmark on an 8-way machine running 2.4.2 SMP kernel. Even when the > priority is reniced to the highest possible value, I am still unable to reach > more than 50% CPU utilization. My benchmark just creates a bunch of threads > with pthread_create(), and then runs a simple integer computation in each > thread. On a dual with 2.4.3 kernel, and a 4-way with 2.4.2 kernel, I am able > to reach full CPU utilization.
I haven't had any problem fully utilizing 8 CPUs on 2.4.* kernels. This may seem obvious, but do you have more than 4 CPUs worth of work for the system to do? What is the runqueue length during this benchmark?
-- Mike Kravetz mkravetz@sequent.com IBM Linux Technology Center - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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