Re: Wierd context-switching issue on Xeon

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От Tom Lane
Тема Re: Wierd context-switching issue on Xeon
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Msg-id 13960.1082341222@sss.pgh.pa.us
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Ответ на Re: Wierd context-switching issue on Xeon  (Dave Cramer <pg@fastcrypt.com>)
Ответы Re: Wierd context-switching issue on Xeon  (Tom Lane <tgl@sss.pgh.pa.us>)
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Dave Cramer <pg@fastcrypt.com> writes:
> So the the kernel/OS is irrelevant here ? this happens on any dual xeon?

I believe so.  The context-switch behavior might possibly be a little
more pleasant on other kernels, but the underlying spinlock problem is
not dependent on the kernel.

> What about hypterthreading does it still happen if HTT is turned off ?

The problem comes from keeping the caches synchronized between multiple
physical CPUs.  AFAICS enabling HTT wouldn't make it worse, because a
hyperthreaded processor still only has one cache.

            regards, tom lane

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