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Date: Thu, 11 Dec 2003 05:32:07 -0800
From: William Lee Irwin III <wli@holomorphy.com>
To: Nick Piggin <piggin@cyberone.com.au>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
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Subject: Re: [CFT][RFC] HT scheduler
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William Lee Irwin III wrote:
>> It will get contention anyway if they're all pounding on the same futex.
>> OTOH, if they're all threads in the same process, they can hit other
>> problems. I'll try to find out more about hackbench.


On Fri, Dec 12, 2003 at 12:30:07AM +1100, Nick Piggin wrote:
> Oh, sorry I was talking about volanomark. hackbench AFAIK doesn't use
> futexes at all, just pipes, and is not threaded at all, so it looks like
> a different problem to the volanomark one.
> hackbench runs into trouble at large numbers of tasks too though.

Volano is all one process address space so it could be ->page_table_lock;
any chance you could find which spin_lock() call the pounded chunk of the
lock section jumps back to?


-- wli