Messages in this thread |  | | Date | Tue, 19 Aug 2008 13:44:04 +0200 | | From | Ingo Molnar <> | | Subject | Re: [PATCH 0 of 9] x86/smp function calls: convert x86 tlb flushes to use function calls [POST 2] |
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* Nick Piggin <nickpiggin@yahoo.com.au> wrote:
> On Tuesday 19 August 2008 20:20, Ingo Molnar wrote: > > * Nick Piggin <nickpiggin@yahoo.com.au> wrote: > > > I'm especially sore about mmap because I have a customer with a > > > database that uses a lot of mmap/munmap and those calls have slowed > > > down something like 50%(!!) from 2.6.early to 2.6.late. > > > > oh, agreed that it all needs to speed up - please send testcases ... > > I'm not sure if I can send the testcase I have. But this issue is > coming to the top of my list to investigate in mainline, so I'll check > out how we're doing here soon.
obviously having a repeatable testcase would jump-start any efforts to fix this. It doesnt have to be complex - just a .c thing kernel developers can run and get some quick number out of. A 50% regression shouldnt be too hard to reproduce even with a vastly simplified workload.
Ingo
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