Messages in this thread | | | Subject | Re: [Bugme-new] [Bug 12562] New: High overhead while switching or synchronizing threads on different cores | From | Peter Zijlstra <> | Date | Thu, 29 Jan 2009 10:07:28 +0100 |
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On Wed, 2009-01-28 at 23:25 +0100, Thomas Pilarski wrote: > Am Mittwoch, den 28.01.2009, 12:56 -0800 schrieb Andrew Morton: > > > (There's testcase code in the bugzilla report) > > > > (Seems to be a regression) > > There is a regression, because of the improved cpu switching. The > problem exists in every kernel.
This is a contradiction in terms - twice.
If it is a regression, then clearly things haven't improved.
If it is a regression, state clearly when it worked last. If it never worked, it cannot be a regression.
> I takes a lot of time to switch between the threads, when they are > executed on different cores. > Perhaps of the big buffer size of 512KB?
Of course, pushing 512kb to another cpu means lots and lots of cache misses.
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