#9722: ghcirun004 intermittently fails with ghc: ioManagerWakeup: write: Bad file descriptor -------------------------------------+------------------------------------- Reporter: ezyang | Owner: simonmar Type: bug | Status: new Priority: high | Milestone: 7.10.1 Component: Runtime System | Version: 7.9 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime crash | Unknown/Multiple Blocked By: | Test Case: ghcirun004 Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Changes (by thomie): * cc: simonmar (added) * owner: => simonmar * component: GHCi => Runtime System Comment: I can reproduce the notorious 'ioManagerWakeup' bug. Not for `ghci004` itself, but for some other ghci tests. On my puny laptop with only 2 cores, I do the following: 1. Make sure the cpu is plenty busy, by running `ghc -e [0..] > /dev/null` in 3 different shells. 2. Run `make test EXTRA_HC_OPTS='+RTS -I0.1 -RTS' TEST='print002 print003 print006 print007 print008 print010'` For me, all tests always fail with: "ioManagerWakup: write: Bad file descriptor" Step 2 sets the 'GC idle time' for ghci script tests to 0.1 seconds (from the default for GHC/GHCi of 5 seconds, see #3408); the same value that is used for other tests with WAY=ghci (among which `ghci004`). The necessity of step 1 might explain why we don't see the bug when running a single test in isolation, but only when running validate, which runs a lot of tests at the same time. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9722#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler