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Date: Thu, 19 Feb 2015 09:41:03 -0800
From: Andi Kleen <ak@linux.intel.com>
To: Adrian Hunter <adrian.hunter@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        linux-kernel@vger.kernel.org, David Ahern <dsahern@gmail.com>,
        Frederic Weisbecker <fweisbec@gmail.com>, Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@gmail.com>, Paul Mackerras <paulus@samba.org>,
        Stephane Eranian <eranian@google.com>,
        John Stultz <john.stultz@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>, Pawel Moll <pawel.moll@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH 0/2] perf/x86: Add ability to sample TSC
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> > And NTP limits the slew rate to 500 PPM, so even if you would get a

Assuming you run NTP

> 
> Assuming it is not broken.

It could also easily switch to HPET if the kernel decides the TSC has some
issues (which may be true or not). 

The switching of the perf clock to MONOTONIC is a bad idea imho.

-Andi