Re: Increasing number of worker tasks in RTS (GHC 7.4.1) - how to debug?

2012-02-28 Thread Sanket Agrawal
> > What version of GHC is this? I vaguely remember fixing something like >> this. > > > The rule of thumb is: if you think it is a bug then report it, and we'll > investigate further. > Simon, it is in GHC 7.4.1. Yes, you fixed a bug #4262 ("GHC's runtime never terminates worker threads"). I hav

Re: Increasing number of worker tasks in RTS (GHC 7.4.1) - how to debug?

2012-02-28 Thread Simon Marlow
On 26/02/2012 02:23, Sanket Agrawal wrote: I have to take back what I said about the increase in worker tasks being related to some Mac OS pthread bug. I can now reproduce the issue on Linux (Redhat x86_64) too (and cause a segmentation fault once in a while). So, now, it seems the issue might be

Re: Increasing number of worker tasks in RTS (GHC 7.4.1) - how to debug?

2012-02-25 Thread Sanket Agrawal
I have to take back what I said about the increase in worker tasks being related to some Mac OS pthread bug. I can now reproduce the issue on Linux (Redhat x86_64) too (and cause a segmentation fault once in a while). So, now, it seems the issue might be due to either some kind of interaction betwe

Re: Increasing number of worker tasks in RTS (GHC 7.4.1) - how to debug?

2012-02-25 Thread Sanket Agrawal
On further investigation, it seems to be very specific to Mac OS Lion (I am running 10.7.3) - all tests were with -N3 option: - I can reliably crash the code with seg fault or bus error if I create more than 8 threads in C FFI (each thread creates its own mutex, for 1-1 coordination with Haskell t

Increasing number of worker tasks in RTS (GHC 7.4.1) - how to debug?

2012-02-25 Thread Sanket Agrawal
I wrote a program that uses a timed thread to collect data from a C producer (using FFI). The number of threads in C producer are fixed (and created at init). One haskell timer thread uses threadDelay to run itself on timed interval. When I look at RTS output after killing the program after couple