ep_testsuite timing out (last test: test dcp consumer flow control aggressive)

During ep-engine commit-validation (http://factory.couchbase.com/job/ep-engine-gerrit-master-multi/992/label_exp=sherlocker-ubuntu12.04/console) I'm seeing ep-testsuite timeout (after 1500 seconds).

Unfortunately there isn't any timestamps on individual tests, but the last test to start is dcp consumer flow control aggressive:

Running [0268/0342]: test dcp consumer flow control aggressive (couchstore)...

Given this is a recent addition it's probably a good place to start looking...