Possible bug related to stm and exceptions

Carter Schonwald carter.schonwald at gmail.com
Thu Oct 17 02:29:21 UTC 2013


I remember Luite mentioning that when he and Ryan Yates where working out
STM for GHCJS, that they  had found some bugs in STM in ghc (presumably now
fixed in head?), have you been able to reproduce the problem in head?

theres also some issues with STM relating to fairness, could you be hitting
a fairness issue?


On Wed, Oct 16, 2013 at 9:01 PM, Andreas Voellmy
<andreas.voellmy at gmail.com>wrote:

> Hi all,
>
> I have a program that uses STM heavily and also performs lots of foreign
> calls. I've noticed that sometimes the program uses 100% CPU indefinitely
> and uses lots of memory - I see it go up to about 5GB before I kill it.
> I've grabbed some preliminary samples of stack traces and see lots stm
> related stuff (e.g. lots of stg_atomically_frame_info and
> stmCommitTransaction entries).  I can pretty reliably get the behavior to
> happen now by closing a socket that my Haskell program is trying to recv
> from. When this causes an exception to be raised (something like "recv:
> resource vanished (Connection reset by peer)") , then this behavior gets
> triggered.  I haven't pinned down the bug yet, but I'm suspecting it is STM
> related - somehow the exception causes some STM transaction to go wrong.
>
> Are there any known bugs that sound similar to this?
>
> BTW, this is with GHC 7.6.3 from a recent HP release on OS X.
>
> -Andi
>
>
>
> _______________________________________________
> ghc-devs mailing list
> ghc-devs at haskell.org
> http://www.haskell.org/mailman/listinfo/ghc-devs
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/ghc-devs/attachments/20131016/56d126a3/attachment.html>


More information about the ghc-devs mailing list