Messages in this thread | | | Date | Tue, 5 May 2015 21:22:25 +0200 | From | Borislav Petkov <> | Subject | Re: [PATCH 207/208] x86/fpu: Add FPU performance measurement subsystem |
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On Tue, May 05, 2015 at 12:15:00PM -0700, Dave Hansen wrote: > On 05/05/2015 10:58 AM, Ingo Molnar wrote: > > x86/fpu: Cost of: XSAVE insn : 104 cycles > > x86/fpu: Cost of: XRSTOR insn : 80 cycles > > Isn't there going to be pretty huge variability here depending on how > much state you are xsave/xrstor'ing and if the init/modified > optimizations are in play?
If this is a module, one could modprobe/rmmod it multiple times for an average. But yeah, it would depend in the end on what the system does/has been doing in the recent past and thus how much state has been "accumulated".
-- Regards/Gruss, Boris.
ECO tip #101: Trim your mails when you reply. --
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