Windows build time: 50% longer....

[Norbert Thiebaud]

On Wed, Jun 17, 2015 at 2:56 AM, Stephan Bergmann <sbergman at redhat.com> wrote:
> On 06/17/2015 09:31 AM, Norbert Thiebaud wrote:
>>
>> On Wed, Jun 17, 2015 at 2:10 AM, Stephan Bergmann <sbergman at redhat.com>
>> wrote:
>>>
>>> On 06/17/2015 01:58 AM, Norbert Thiebaud wrote:
>>>>
>>>>
>>>> most likely candidate is prolly:
>>>>
>>>> 9b06d36571bbfa2d722f36610375e7cd24be81a7 reenable
>>>> JunitTest_dbaccess_complex part RowSet
>>>
>>>
>>>
>>> ...which should be easy to verify with "time make
>>> JunitTest_dbaccess_complex" vs. "git revert
>>> 9b06d36571bbfa2d722f36610375e7cd24be81a7 && time make
>>> JunitTest_dbaccess_complex", no?
>>
>>
>> Not when you have a build queue of 25 jobs, and are scrambling to
>> bring some ressource online to try to drain that queue before people
>> wake up and pile up again....
>>
>> iow 100% of the Windows I have access are working hard to keep up... I
>> do not have spare to do this 'easy' thing....
>>
>> I've narrowed it down to about 20 commits using build history data..
>> that, I could do without stopping builders....
>
>
> for my random Windows 64-bit --enable-dbgutil etc. build, time values as per
> above are
>
>   real 2m26.160s
>   user 0m0.000s
>   sys  0m0.000s
>
> vs.
>
>   real 0m46.872s
>   user 0m0.000s
>   sys  0m0.000s

Thanks.

That does not account entirely for the slow down...   beside, and I
should have realized that earlier, gerrit build do not do make check.
I could not find (duh!) any impact on tb16 by removing that test on a
gerrit build time make (on an already fully built tree)

The latest few runs on tb65 clock at 41 minutes  that is 10-11 minutes
slower than it used to be .... but the latest run on tb16 (which I
brought back on gerrit duties yesterday to cope with the load, clock
at 42m
which is in line with historical performances...
so the degradation seems to be more system related than code
related... somehow the ec2 machine is getting slower over time....

I'll try to apply a 'windows support' technique to it.. and 'reboot'
to see if that has an impact on build time...

Norbert