#3758: Huge regression in concurrent app performance and reliability under
threaded runtime
-----------------------------+----------------------------------------------
Reporter: bos | Owner: simonmar
Type: bug | Status: new
Priority: high | Milestone: 6.12.2
Component: Runtime System | Version: 6.12.1
Resolution: | Keywords:
Difficulty: | Os: Linux
Testcase: | Architecture: x86_64 (amd64)
Failure: Runtime crash |
-----------------------------+----------------------------------------------
Comment (by simonmar):
I'll investigate some more, but what I think is happening is that we're
only really using one core at a time, and the other core is mostly asleep
(the !ThreadScope profile confirms this). Hence, when using the parallel
GC we have to keep waking up the second core and waiting for it, when in
fact it would be better to just do a single-threaded GC.
Now, I don't understand yet why the benchmark isn't keeping both cores
busy, but we ought to be able to debug that using !ThreadScope.
Are you still seeing the deadlocks, BTW? I couldn't reproduce that on my
dual-core laptop running Ubuntu Karmic (32-bit).
--
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3758#comment:9>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler
_______________________________________________
Glasgow-haskell-bugs mailing list
[email protected]
http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
