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SubjectRe: [PATCH] tools, perf: Allow the user to disable time stamps
On Tue, Mar 25, 2014 at 10:01 PM, Andi Kleen <> wrote:
>> Timestamp are useful to order samples during reporting.
>> How do you do with it if you monitor multi-threaded (multi-cpu)
>> workloads. This is only good for single thread or single CPU
>> measurements. Or am I missing something?
> For a perf report order doesn't matter (except against mmaps)
> The CPUs are still separated of course
But getting the mmaps at the right moment is crucial for some apps
especially if address space is recycled otherwise symbolization
may be incorrect.

> You're right for some special analysis it matters, that is why
> it is only an option.
> But for the standard "only care about perf report and
> don't care about about program startup" case it's a nice saving.
How do you know in advance you won't need mmap ordering?

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