[gecode-users] Multiple thread lock error

[Guido Tack]

Chris Mears wrote:

> Hello all,
> 
> Sometimes when running an example (e.g. ./bibd -threads 4) with more
> than one thread I provoke this error at the end:
> 
>  terminate called after throwing an instance of 'Gecode::OperatingSystemError'
> 
> ... or sometimes this one:
> 
>  terminate called after throwing an instance of 'Gecode::OperatingSystemError'
>    what():  Mutex::acquire[pthread_mutex_lock]: Operating system error
>  Aborted
> 
> It happens only some of the time, with Gecode 3.4.0 and with the trunk
> version, on Debian Linux with kernel version 2.6.32.

Could you give us some details on the machine (processor(s), how many cores, hyperthreading)?

> Is this a serious error?  It still seems to give the right answer
> before it prints the error.

I don't think the concurrency problems can lead to wrong answers at the moment, but this should be fixed anyway.  Can you run it in gdb and send us the stack traces of all the threads when the program crashes?  Thanks!

Guido

-- 
Guido Tack, http://people.cs.kuleuven.be/~guido.tack/