[Python-Dev] "Buildbot" category on the tracker

[exarkun at twistedmatrix.com]

On 12:55 pm, jnoller at gmail.com wrote:
>On Fri, Oct 30, 2009 at 4:53 AM, "Martin v. Löwis" <martin at v.loewis.de> 
>wrote:
>>I'm confused: first you said they fail, now you say they get skipped.
>>Which one is it? I agree with R. David's analysis: if they fail, it's
>>a multiprocessing bug, if they get skipped, it's a flaw in the build
>>slave configuration (but perhaps only slightly so, because it is good
>>if both cases are tested - and we do have machines also that provide
>>/dev/shm).
>
>They failed until we had the tests skip those platforms - at the time,
>I felt that it was more of a bug with the build slave configuration
>than a multiprocessing issue, I don't like skipping tests unless the
>platform fundamentally isn't supported (e.g. broken semaphores for
>some actions on OS/X) - linux platforms support this functionality
>just fine - except when in locked-down chroot jails.
>
>The only reason I brought it up was to point out the a buildbot
>configuration on a given host can make tests fail even if those tests
>would normally pass on that operating system.

Just as a build slave can be run in a chroot, so can any other Python 
program.  This is a real shortcoming of the multiprocessing module. 
It's entirely possible that people will want to run Python software in 
chroots sometimes.  So it's proper to acknowledge that this is an 
unsupported environment.  The fact that the kernel in use is the same as 
the kernel in use on another supported platform is sort of irrelevant. 
The kernel is just one piece of the system, there are many other 
important pieces.

Jean-Paul