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Subject: Re: [PATCH v5 00/20] Introduce threaded trace streaming for basic
 perf record operation
To:     Namhyung Kim <namhyung@kernel.org>,
        Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Alexander Antonov <alexander.antonov@linux.intel.com>,
        Alexei Budankov <abudankov@huawei.com>
References: <cover.1619781188.git.alexey.v.bayduraev@linux.intel.com>
 <CAM9d7citW_NGb0vjMM2ytp=Mbq5YNe4GEaWspEkMGf=KAm+ugw@mail.gmail.com>
From:   Andi Kleen <ak@linux.intel.com>
Message-ID: <4926ae4f-b14b-1048-229b-0b789204c192@linux.intel.com>
Date:   Thu, 6 May 2021 07:17:17 -0700
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On 5/5/2021 11:20 PM, Namhyung Kim wrote:
>
> Do you have an idea how to improve it?
>
> I have to say again that I don't like merely adding more threads to
> record.  Yeah, parallelizing the perf record is good, but we have to
> think about the perf report (and others) too.

perf report/script can be already parallelized with --time xx/x% and a 
simple shell script that runs multiple processes. While that's a bit 
awkward for interactive use it works fine for scripting. I use it all 
the time for PT batch processing for example. The real bottleneck we 
have is really record on systems with many CPUs (which are more and more 
common), and that can only be fixed with some variant of this patch kit.

-Andi