i would like to comment on r31738 :
> There is no reason to cancel the listening thread. It should die
> automatically when the file descriptor is closed.
i could not agree more
> It is sufficient to just wait for the thread to exit with pthread join.
unfortunatly, at least in my test environment (an outdated MPSS 2.1) it
is *not* :-(
this is what i described in #4615
in which i attached scif_hang.c that evidences that (at least in my
scif_poll(...) does *not* return after scif_close(...) is closed, and
hence the scif pthread never ends.
this is likely a bug in MPSS and it might have been fixed in earlier
Nathan, could you try scif_hang in your environment and report the MPSS
version you are running ?
bottom line, and once again, in my test environment, pthread_join (...)
might cause a hang when the btl/scif module is released.
assuming the bug is in old MPSS and has been fixed in recent releases,
what is the OpenMPI policy ?
a) test the MPSS version and call pthread_cancel() or do *not* call
pthread_join if buggy MPSS is detected ?
b) display an error/warning if a buggy MPSS is detected ?
c) do not call pthread_join at all ? /* SIGSEGV might occur with older
MPSS, it is in MPI_Finalize() so impact is limited */
d) do nothing, let the btl/scif module hang, this is *not* an OpenMPI
problem after all ?
e) something else ?