Hi Dave,

Le 03/06/2015 03:15, David T. Lewis a ��crit :

Hi Thierry and Jose,

I am reading this thread with interest and will help if I can.

I do have one idea that we have not tried before. I have a theory that this may
be an intermittent problem caused by SIGCHLD signals (from the external OS process
when it exits) being missed by the UnixOSProcessAccessor>>grimReaperProcess
that handles them.

If this is happening, then I may be able to change grimReaperProcess to
work around the problem.

When you see the OS deadlock condition, are you able tell if your Pharo VM
process has subprocesses in the zombie state (indicating that grimReaperProcess
did not clean them up)? The unix command "ps -axf | less" will let you look
at the process tree and that may give us a clue if this is happening.

I found it very easy to reproduce and I do have a zombie children process to the pharo process.

Interesting enough, the lock-up happens in a very specific place, a call to git branch, which is a very short command returning just a few characters (where all other commands have longuer outputs). Reducing the frequency of the calls to git branch by a bit of caching reduces the chances of a lock-up.

Thanks,

Dave

Thanks!

Dave