From mboxrd@z Thu Jan  1 00:00:00 1970
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Subject: Re: vpmu=1 and running 'perf top' within a PVHVM guest
 eventually hangs dom0 and hypervisor has stuck vCPUS. Romley-EP (model=45,
 stepping=2)
Date: Wed, 13 Mar 2013 15:59:43 -0400
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On 03/12/2013 04:54 PM, Boris Ostrovsky wrote:
>
> I think by default perf top runs off timer interrupt so it does not 
> use HW counters. But watchdog
> is implemented on top of the counters so perhaps it fires the 
> interrupt at a bad time, messing
> something up.
>

I was wrong -- perf top does use performance counters by default.

-boris