[Swift-devel] Lammps on BGQ: task completes but status shows active

[Mihael Hategan]

On Mon, 2014-12-08 at 14:07 -0600, Ketan Maheshwari wrote:
> I tried to get strace output with two methods:
> 
> stderr.txt: This was obtained by attaching the "--strace 0" switch to the
> runjob command. It seems to be exiting normally after writing a bunch of
> stuff.
> 
> strace.out: This one was obtained by wrapping the app exe with strace -o
> $HOME/strace.out  ...

Are you sure? It looks like you wrapped the execution of bg.sh in
strace. This log only tells us that bg.sh starts runjob and runjob never
completes, which we already know. You probably want to go to the lowest
level possible. But see below (*).

> 
> This one shows a stuck output with the last line as:
> 
> waitpid(-1, %

waitpid means it's waiting for a subprocess, so this isn't useful
because we want to find out what the leaf subprocess is hanging on. You
could use the '-f' argument to strace to make it follow subprocesses. If
you do that, it probably won't matter (aside from noise) at what level
you use strace (*).

Mihael