linux-kernel - Re: [PATCH v8 0/3]: perf: reduce data loss when profiling highly parallel CPU bound workloads

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Date:   Mon, 10 Sep 2018 12:03:03 +0200
From:   Ingo Molnar <mingo@...nel.org>
To:     Jiri Olsa <jolsa@...hat.com>
Cc:     Alexey Budankov <alexey.budankov@...ux.intel.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Namhyung Kim <namhyung@...nel.org>,
        Andi Kleen <ak@...ux.intel.com>,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v8 0/3]: perf: reduce data loss when profiling highly
 parallel CPU bound workloads


* Jiri Olsa <jolsa@...hat.com> wrote:

> > Per-CPU threading the record session would have so many other advantages as well (scalability, 
> > etc.).
> > 
> > Jiri did per-CPU recording patches a couple of months ago, not sure how usable they are at the 
> > moment?
> 
> it's still usable, I can rebase it and post a branch pointer,
> the problem is I haven't been able to find a case with a real
> performance benefit yet.. ;-)
> 
> perhaps because I haven't tried on server with really big cpu
> numbers

Maybe Alexey could pick up from there? Your concept looked fairly mature to me
and I tried it on a big-CPU box back then and there were real improvements.

Thanks,

	Ingo