[Buildbot-devel] using buildbot on a single machine doing cross compilation builds

[Tobi Vollebregt]

On Monday 07 January 2008 12:22:13 Max Horn wrote:
> Hi there,
> 
> we (the ScummVM team <http://www.scummvm.org>) are currently investigating
> the possibility of setting up an automated build server. We have lots of
> target platforms (see <http://wiki.scummvm.org/index.php/Platforms> to get
> an idea), and many require cross compilation.
> 
> My questions:
> 1) How well does BuildBot support building stuff in a cross compilation
> environment? Specifically, we would probably have to use some custome env
> vars for each platform (e.g. a modified PATH so that it finds the right
> compiler variant). Has anybody experience with that, is BuildBot suitable
> for this?

You can specify environment variables per build step. It is also possible to 
use a wrapper script that exports the right environment variables and then 
calls the buildsystem.

> 2) Is using a single machine supported, or does BuildBot *require* us to
> use a build farm? We do not have that much money, so right now a single
> machine is all we can afford to rent. On the other hand, we'd be fine with
> running our platform builds sequentially, so don't mind if it takes an
> hour or more for them to finish. My main concern here is: Does BuildBot
> support the possibility of running multiple different builds (based on the
> same source, just targeting a different architecture) on a single build
> slave (which would be identical to the build master)? Ideally, in
> sequence, to avoid overloading the server resources with a dozen parallel
> builds...

You can do everything on one machine, the buildbot I set up for the open 
source strategy game Spring (http://buildbot.no-ip.org:8010) runs with a 
single slave, which builds for linux (several builds with different configure 
options), mingw with GCC 4.2 and mingw with GCC 4.3.

You can use locking to ensure only a single build is running on the buildslave 
at a time, I used this too to spare the server resources a bit.

(and the old server I used was so extremely weak it almost died if two builds 
were at the linking stage at the same time: it caused lots of swapping and 
usually a timeout (20 min no output) of one of the builds)

> 3) Is there an IRC channel or so where I can get some online help while
> setting up the server, should the answers to the two questions above be
> affirmative?
> 
> Thanks a lot for your help,
> Max

Tobi