Hello Robert,

> My problem is similar to the one discussed in a thread here in April,
> though I have not solved it. My system is based on the AMD FX-8350
> CPU, which should have either 4 or eight cores depending on whether
> they are physical or virtual. The OS is Ubuntu 17.04 Zesty Zapus
> (x64), released a couple of weeks ago. I followed the Simplified
> Tutorial, with everything pasted in without alteration. (The
> exception is that 'mpich' is apparently required instead of
> 'mpich2.') 
Good to know. I'll update the tutorial, just have to understand how
to make it work with the LTS and current releases and ideally both 17
and 16.

> The graphical output is exactly the same as that presented
> on the Website, as near as I can tell. When computation starts, it
> says it's using one thread, instead of the same number as the number
> of processors, as I was led to believe. I then set the environment
> variable: export OMP_NUM_THREADS=4 and verified it with printenv, but
> it's still using only one thread. (It took about five hours to
Hmm, so given that printenv worked and showed the OMP_NUM_THREADS is
the expected value it should also show up in Carpet's output (and you
have eliminated ~75% of the usual causes). Can you attach the *.out
file, please? 

Given that you said you followed the simplified tutorial which uses
simfactory, OMP_NUM_THREADS is likely not respected since the
debian.run file overwrites it. Instead when using simfactory to
start the simulation did you specify a --num-threads option? Like so:

simfactory/bin/sim submit static_tov --parfile par/static_tov.par
--procs 1 --num-threads 4 ?

This may actually fail stating that there are not enough cores on you
laptop since simfactory (I think) defaults to assuming only a single
core. You may have to add "--mdbentry max-num-threads 4 --mdb-entry ppn
4" as well. This should likely be changed in simfactory.

Please do not use --procs 4 --num-threads 4 or similar since the number
of cores used with be --procs (number of processes) times --num-threads
(numer of threads per process) though that would give you a different
output in Carpet.

Yours,
Roland


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