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Re: [PATCH] Converted benchmark to benchtest.
- From: Siddhesh Poyarekar <siddhesh dot poyarekar at gmail dot com>
- To: OndÅej BÃlka <neleai at seznam dot cz>
- Cc: Torvald Riegel <triegel at redhat dot com>, Siddhesh Poyarekar <siddhesh at redhat dot com>, "Carlos O'Donell" <carlos at redhat dot com>, Andi Kleen <andi at firstfloor dot org>, GNU C Library <libc-alpha at sourceware dot org>
- Date: Fri, 6 Jun 2014 02:55:15 +0530
- Subject: Re: [PATCH] Converted benchmark to benchtest.
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On 6 June 2014 01:24, OndÅej BÃlka <neleai@seznam.cz> wrote:
>> "pthread_rwlock_test": {
>> "rwlock": {
>> "duration": 2.87958e+09,
>> "iterations": 2.7688e+07,
>> "max": 172.944,
>> "min": 97.516,
>> "mean": 104.001
>> },
>> "rdlock": {
>> "duration": 2.88252e+09,
>> "iterations": 2.7022e+07,
>> "max": 252.66,
>> "min": 101.541,
>> "mean": 106.673
>> }
>> }
>>
> It is that you must always look for ways that could make benchmark
> invalid.
> Also I noticed that this takes long to run, did you also noticed that?
The standard benchmarks run only for BENCH_DURATION time and the above
was for 1 second, so I'm not sure how I should be concluding whether
it 'takes long' or not.
> That is true to some extend, but lets assume that we check this patch in
> other way and commit your benchmark. Do you thing that next time when
> there comes a patch touching rdlocks somebody will do a comparison if
> nobody did it first time?
Why not? That is the point of the microbenchmarks - if there is a
significant change in a function and there's a microbenchmark for it,
the submitter should post the before and after results of the change.
Since we don't have any disagreement over the approach and the
generated code also is not a problem (as you pointed out in your other
response) there should be no problem with getting the benchmark in and
letting Andi use it to compare the before and after results.
I don't even mind waiting for Andi to revert with results before
committing the benchmark if that's what you want.
Siddhesh
--
http://siddhesh.in