Avoid sendGo if the FSHookHandler threw an exception
TODO
Oops: Printer's putStrLn for String was an infinite loop
Oops: modifyMVarMasked was used which masked way too many things
ghc-prof-options: Use -threaded as well
Make sure AsyncContext is not used outside valid scope
TODO
Rewrite input/output discovery/recording
Add tests for scratch output files
Factor out SEND_MSG_AWAIT
Fix test of over-parallelization. Move it from example to test/overpar.
Parallelism: Inline localReleasePool
Oops: Non-atomic use of IORef masked over-parallelism bugs
Convert Parallelism cell to be MVar: Fix over-parallelism bug
TODO
writeBack of db file is supposed to be a short potentially blocking operation inside end of bracket. Use uninterruptibleMask_
Slave.wait: Take no printer. Cancel all slaves does a quicker 2-pass
cancelAllSlaves: Disallow exceptions
Implement -k keepgoing
fs_override: Instead of ASSERT failures upon server death, propagate errors instead of executing libc FS access calls