Power8 VMs have really little available disk space, like 30-50Gb (minus space taken by OS). Each of them keep 3 build directories: release, debug and packages. Each directory is up to 7Gb, which gives 21Gb.
This makes builds hit out of disk errors frequently. Please add a step to bb configuration to cleanup build dir when build is completed. Or solve this problem any other reasonable way.
Also please remove "xtra" step, it is covered anyway by "xtra-big".
There's also AT7.x and AT8.x installed on p8-rhel7, which take almost 5Gb. Worth to remove one version?