Re: [tip:perf/urgent] perf/x86: Enable raw event access to Inteloffcore events

[Stephane Eranian]

Vince,

On Mon, Nov 21, 2011 at 8:01 PM, Vince Weaver <vweaver1@xxxxxxxxxxxx> wrote:
> On Mon, 21 Nov 2011, Peter Zijlstra wrote:
>> On Mon, 2011-11-21 at 13:24 -0500, Vince Weaver wrote:
>
>> > Now I'll have to find something else
>> > to complain about, probably the scedulability issue introduced with the
>> > NMI watchdog.
>>
>> But you can disable that thing, right?
>>
>> echo 0 > /proc/sys/kernel/nmi_watchdog;
>>
>> or so should do the trick.
>
> yes, if the user running PAPI has root.
>
> That's unfortunately not always the case, and sometimes people want to
> have both the NMI watchdog operating and use PAPI simultaneously.
>

I don't understand why you have a problem with NMI watchdog. Multiplexing
allows you to still measure more events than there are counters.

> We have a workaround, but it currently disables kernel multiplexing and a
> few other nice features.
>
> Vince
> vweaver1@xxxxxxxxxxxx
>
>
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