Clobbering the trees
Today we landed some changes that will give developers self-serve clobber ability on our Mozilla Central / Mozilla 1.9.1 / Tracemonkey infrastructure. In our current infrastructure, we have a large pool of slave machines for each platform that each build all the various branches. This makes it nice and easy to spin up new project and release branches, and automatically distributes jobs across branches. However, it can sometimes be confusing when tracking down a build or test failure. Sometimes, a particular machine needs to have its build directory cleaned out; and sometimes all the machines for one branch or build type need to be cleaned up. Until now, this could only be done by RelEng by accessing the build machines directly. But now you can do it too! If you've got a valid LDAP account, head on over to http://build.mozilla.org/clobberer. You'll see a giant table, with lots of checkboxes on it. If you check a box next to one of the slaves on a particular branch / builder, then the next time that slave runs a build on that branch, it will first delete the entire build directory, and then do a fresh checkout, and continue on with the rest of the build. Selecting a builder-level checkbox merely selects all the slaves for that builder, and similarly, selecting the branch-level checkbox selects all the slaves for all the builders in that branch. In addition, if a slave has not been clobbered in a configurable time period (currently set to 1 week), it will clobber on the next run. Slaves are added to the database as they report in to ask for their clobber data, so it could take a little while for all the slave / builder / branch combinations to show up. See bug 432236 for more information.