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Date: Thu, 6 Jun 2024 10:15:00 +0530
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From: Ravi Bangoria <ravi.bangoria@amd.com>
Subject: Re: [PATCH v1] perf top: Make zeroing histogram on refresh the
 default
To: Ian Rogers <irogers@google.com>, Ingo Molnar <mingo@redhat.com>,
 Arnaldo Carvalho de Melo <acme@kernel.org>,
 Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>, Mark Rutland
 <mark.rutland@arm.com>,
 Alexander Shishkin <alexander.shishkin@linux.intel.com>,
 Jiri Olsa <jolsa@kernel.org>, Adrian Hunter <adrian.hunter@intel.com>,
 Kan Liang <kan.liang@linux.intel.com>, Changbin Du <changbin.du@huawei.com>,
 John Fastabend <john.fastabend@gmail.com>,
 Andrii Nakryiko <andrii@kernel.org>, linux-perf-users@vger.kernel.org,
 linux-kernel@vger.kernel.org, Stephane Eranian <eranian@google.com>,
 ravi.bangoria@amd.com
References: <20240516222159.3710131-1-irogers@google.com>
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On 5/17/2024 3:51 AM, Ian Rogers wrote:
> Instead of decaying histograms over time change it so that they are
> zero-ed on each perf top refresh. Previously the option '-z', or
> pressing 'z' in tui mode, would enable this behavior. Decaying samples
> is non-intuitive as it isn't how "top" works. Make zeroing on refresh
> the default and rename the command line options from 'z' to 'Z' and
> 'zero' to 'decay'.
I've also felt `perf top` decay as non-intuitive. Esp. when system becomes
idle after some heavy workload, even decayed samples are far more compared
to samples from currently running processes and thus `perf top` keeps
showing already finished processes at the top, which is kind of confusing.
fwiw:

Acked-by: Ravi Bangoria <ravi.bangoria@amd.com>