From: Qu Wenruo <quwenruo.btrfs@gmx.com>
To: Dave Chinner <david@fromorbit.com>
Cc: fstests <fstests@vger.kernel.org>
Subject: Re: Any way to detect performance in a test case?
Date: Wed, 23 Jan 2019 13:08:30 +0800 [thread overview]
Message-ID: <903e8afa-413a-b0c9-5c91-682691107fbe@gmx.com> (raw)
In-Reply-To: <20190123041830.GQ6173@dastard>
[-- Attachment #1.1: Type: text/plain, Size: 2149 bytes --]
On 2019/1/23 下午12:18, Dave Chinner wrote:
> On Wed, Jan 23, 2019 at 08:51:03AM +0800, Qu Wenruo wrote:
>>
>>
>> On 2019/1/17 上午10:25, Dave Chinner wrote:
>>> On Thu, Jan 17, 2019 at 09:30:19AM +0800, Qu Wenruo wrote:
>>>> On 2019/1/17 上午8:16, Dave Chinner wrote:
>>>>> On Wed, Jan 16, 2019 at 12:47:21PM +0800, Qu Wenruo wrote:
>>>>>> E.g. one operation should finish in 30s, but when it takes over 300s,
>>>>>> it's definitely a big regression.
>>>>>>
>>>>>> But considering how many different hardware/VM the test may be run on,
>>>>>> I'm not really confident if this is possible.
>>>>>
>>>>> You can really only determine performance regressions by comparing
>>>>> test runtime on kernels with the same features set run on the same
>>>>> hardware. Hence you'll need to keep archives from all your test
>>>>> machiens and configs and only compare between matching
>>>>> configurations.
>>>>
>>>> Thanks, this matches my current understanding of how the testsuite works.
>>>>
>>>> It looks like such regression detection can only be implemented outside
>>>> of fstests.
>>>
>>> That's pretty much by design. Analysis of multiple test run results
>>> and post-processing them is really not something that the test
>>> harness does. The test harness really just runs the tests and
>>> records the results....
>>
>> What about using some other telemetry other than time to determine
>> regreesion?
>>
>> In my particular case, the correct behavior, some reading like
>> generation would only increase by a somewhat predictable number.
>>
>> While when the regression happens, the generation will go way higher
>> than expectation.
>
> That's something that would be done inside the test, right? i.e.
> this has nothing to do with the test harness itself, but is a
> failure criteria for the specific test?
Yep, a failure criteria for that specific test.
>
>> Is it acceptable to craft a test case using such measurement?
>
> If it's reliable and not prone to false positives from future code
> changes, yes.
Glad to know that.
Thanks,
Qu
>
> Cheers,
>
> Dave.
>
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
prev parent reply other threads:[~2019-01-23 5:08 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-16 1:59 Any way to detect performance in a test case? Qu Wenruo
2019-01-16 3:57 ` Dave Chinner
2019-01-16 4:47 ` Qu Wenruo
2019-01-16 17:33 ` Vijaychidambaram Velayudhan Pillai
2019-01-17 0:16 ` Dave Chinner
2019-01-17 1:30 ` Qu Wenruo
2019-01-17 2:25 ` Dave Chinner
2019-01-23 0:51 ` Qu Wenruo
2019-01-23 4:18 ` Dave Chinner
2019-01-23 5:08 ` Qu Wenruo [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=903e8afa-413a-b0c9-5c91-682691107fbe@gmx.com \
--to=quwenruo.btrfs@gmx.com \
--cc=david@fromorbit.com \
--cc=fstests@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox