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Date:   Mon, 14 Mar 2022 11:55:12 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Wen Yang <wenyang@linux.alibaba.com>
Cc:     Stephane Eranian <eranian@google.com>,
        Wen Yang <simon.wy@alibaba-inc.com>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        mark rutland <mark.rutland@arm.com>,
        jiri olsa <jolsa@redhat.com>,
        namhyung kim <namhyung@kernel.org>,
        borislav petkov <bp@alien8.de>, x86@kernel.org,
        "h. peter anvin" <hpa@zytor.com>, linux-perf-users@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [RESEND PATCH 2/2] perf/x86: improve the event scheduling to
 avoid unnecessary pmu_stop/start
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On Thu, Mar 10, 2022 at 11:50:33AM +0800, Wen Yang wrote:

> As you pointed out, some non-compliant rdpmc can cause problems. But you
> also know that linux is the foundation of cloud servers, and many
> third-party programs run on it (we don't have any code for it), and we can
> only observe that the monitoring data will jitter abnormally (the
> probability of this issue is not high, about dozens of tens of thousands of
> machines).

This might be a novel insight, but I *really* don't give a crap about
any of that. If they're not using it right, they get to keep the pieces.

I'd almost make it reschedule more to force them to fix their stuff.