Re: [PATCH] kselftest/timers: Set default threadtest values to simplify execution scripts

From: Shuah Khan
Date: Thu Mar 19 2015 - 18:49:05 EST


On 03/19/2015 04:34 PM, John Stultz wrote:
> On Thu, Mar 19, 2015 at 3:01 PM, Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> wrote:
>> On 03/18/2015 09:51 AM, John Stultz wrote:
>>> In order to keep the kselftest Makefiles simpler, set the threadtest
>>> default values to the ones used in standard run_tests
>>>
>>> Cc: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
>>> Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
>>> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>>> Cc: Richard Cochran <richardcochran@xxxxxxxxx>
>>> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
>>> ---
>>> tools/testing/selftests/timers/threadtest.c | 8 ++++++--
>>> 1 file changed, 6 insertions(+), 2 deletions(-)
>>>
>>
>> Applied to next for 4.1
>>
>> Some numbers for you with timer tests included:
>>
>> make kselftest target takes:
>>
>> real 11m50.499s
>> user 3m25.979s
>> sys 5m45.433s
>>
>> It is creeping up, previous timing was
>>
>> real 9.41
>> user 3.55
>> system 0:24.86
>>
>> Not concerned yet. Might be getting closer to
>> needing to defining quick vs long test categories.
>
> Yea, the timekeeping tests are particularly rough about how long the
> run. In some cases we're having to watch for behavior that could be
> somewhat rare, so we need to watch for a fair amount of time. In some
> cases we're doing our own calibrations which require a larger amount
> of time to ensure accuracy. And in other cases, we want to have timers
> that fire far enough out that any scheduler variance/noise is easy to
> filter out.
>
> With the destructive tests, which re-run the validation tests
> repeatedly under different conditions, it ends up being about an hour!
> So I feel this pain.
>
> But there's also probably some spots where 3 seconds seemed like a
> good value, but could be shorter. So I'll have to take another look
> to see if we could reasonably compress some of the intervals we use
> down. There may also be some spots where we could parallelize the
> tests across the various clockids.
>

If you can take a look to see which tests can be included in a
quick test run vs. longer test run in addition to destructive
vs. normal. I will work on adding categories soon. The logic
can be isolated in selftest/Makefile and timers/Makefile.

thanks,
-- Shuah

--
Shuah Khan
Sr. Linux Kernel Developer
Open Source Innovation Group
Samsung Research America (Silicon Valley)
shuahkh@xxxxxxxxxxxxxxx | (970) 217-8978
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/