Testing is a very important part of the life of a project such as Squid, especially as we wish to support as many different operating systems and platforms as we can, as efficiently as we can.
This also means that we can’t restrict to well-known POSIX APIs, but we need to account for each OS’s particular quirks and optimizations, especially in those areas where there is the need of a deep integration with the OS.
One of the tools which we have added a few years ago is the build farm. When new code is committed to a followed branch, our Jenkins setup will notice it, and schedule a test run on all the eligible nodes. This means we need to rely on a mix of operating systems, libraries and compilers.
We are always on the lookout for sponsors, both individuals and companies, and back in July Rackspace volunteered to donate space for the Squid project us on their public cloud infrastructure. As of now, we have 11 virtual machines and one database hosted in their cloud, running mostly various flavors of Linux and FreeBSD. The experience has been very satisfying, in particular I’ve found the claim about “fanatical support” to be well-founded in the dedication and kindness of everyone who was involved in making this happen.
It was not all rose petals, of course. Our needs mean that we are better off with something resembling the bare metal, while the model Rackspace offers is more oriented towards having predefined images which configure certain aspects such as network addresses, admin users’ passwords etc.
Still, it is very refreshing that if an OS is among the list of supported images (as an example, Ubuntu Saucy was available about three days after Canonical released it) setting up a new build node in the farm takes literally 15 minutes, most of which is spent waiting for the server image to be cloned from the template.
The first effects of the newly expanded build farm are already apparent: we have reached a stable build status on a wide number of Linux, FreeBSD and OpenBSD versions, with gcc, clang and icc compilers. We are starting to set sight on MacOSX and to bring Squid 3 to Windows. All of this would have been much harder, or even impossible, without the Build Farm.
So on behalf of everyone who works on Squid, I’d like to thank Rackspace for their kind contribution to the Project.
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