[Buildbot-devel] Combining multiple-platform builds

[Dustin J. Mitchell]

On Dec 27, 2007 6:54 PM, Richard Offer <offer at fastscale.com> wrote:
> I have a newbie question…. What are the best practices for combining the
> results of multiple builds for a dependent build stage ?

Not really a newbie question -- it's pretty sophisticated.

> I have three build schedulers, one is used for the main build (across
> multiple builders – one per platform), the other two are follow-on
> (dependent) steps that can only be done once all the first set of builders
> have completed.

You may want to look into triggerable schedulers (and you win a cookie
if you can think of a better name for them).  See
http://buildbot.net/trac/ticket/56.

> I had hoped that I could re-use the build tree from the first stage in the
> subsequent stages – but its seems to get deleted on success. So I have the
> final step in the first build stage copy the results somewhere permanent. I
> then have to re-checkout the source tree for the second and third stages.

I don't think there's any help for that -- as a rule, each builder has
its own directory.  In our setup, we upload a tarball (since the first
build is a "make dist", and most of our builders don't have the
equipment necessary to run autogen), and then download that tarball
in all of the triggered builds.

> But what happens if there is a check-in to the source tree between he first
> and second stages ? I set alwaysUseLatest to False in the SVN() step for
> stage 2 – but it didn't seem to work.

I also ran into this problem.  The solution was what I called
"specific" SourceStamps, but which might be better named "canonical"
or "absolute' SourceStamps.  The idea is that when a scheduler is
triggered, it takes the got_revision from the Source step of the
earlier build, and builds a SourceStamp with a specific revision in it
for use by all of the triggered builds.  See
http://buildbot.net/trac/ticket/71.

Dustin

-- 
Storage Software Engineer
http://www.zmanda.com