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Date:   Wed, 29 Jul 2020 20:57:04 +0300
From:   Vitaly Chikunov <vt@altlinux.org>
To:     Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>,
        peterz@infradead.org
Cc:     Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        linux-kernel@vger.kernel.org, "Dmitry V. Levin" <ldv@altlinux.org>
Subject: Re: Should perf version match kernel version?
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Peter, Arnaldo,

On Wed, Jul 29, 2020 at 01:27:32PM -0300, Arnaldo Carvalho de Melo wrote:
> 
> 
> On July 29, 2020 1:02:20 PM GMT-03:00, peterz@infradead.org wrote:
> >On Wed, Jul 29, 2020 at 06:56:47PM +0300, Vitaly Chikunov wrote:
> >> Hi,
> >> 
> >> It seems that most distros try to have perf version to match with
> >> running kernel version. Is is requirement? Would it be better to have
> >> single perf from kernel mainline to work with any (older) kernel
> >> version?
> >> 
> >> We have different kernel versions in ALT Linux (stable for 4.19, 5.4,
> >> and 5.7) and I want to understand if we should have three perfs or
> >> single package will be enough.
> >
> >We strive to have it all compatible, older perf should work on newer
> >kernel and newer perf should work on older kernel.
> >
> >How well it's all tested is another.
> >
> >Personally I often use a very old perf.
> 
> Yeah, never was a requirement, if you find some problem using a new perf on an old kernel or the other way around, please report.

That's great to know. Thanks for the answers!