Hi! The answer to your question is no, it is not possible.
A task (Linux process) is running on a single node only and can allocate/use only the available CPUs on that node. You need an MPI job (or Hybrid MPI+OpenMP) in order to utilize CPUs on different nodes for a single purpose/application. Best Regards, Chrysovalantis Paschoulas On 09/09/2014 05:14 PM, Michal Zielinski wrote: Phil, I believe that 1 core per node is correct. Maybe let me ask this first: is possible for a single task to use specific CPUs across several nodes? Thanks, Mike On Tue, Sep 9, 2014 at 10:38 AM, Eckert, Phil <ecke...@llnl.gov<mailto:ecke...@llnl.gov>> wrote: Mike, In your slurm.conf you have Procs=1, (which is the same as CPUS=1) and Sockets (if ommited will be inferred from CPUS, default is 1) and CoresPerSocket (default is 1) So at this point the slurm.conf has a default configuration of 1 core per node. Phil Eckert LLNL From: Michal Zielinski <michal.zielin...@uconn.edu<mailto:michal.zielin...@uconn.edu>> Reply-To: slurm-dev <slurm-dev@schedmd.com<mailto:slurm-dev@schedmd.com>> Date: Tuesday, September 9, 2014 at 6:35 AM To: slurm-dev <slurm-dev@schedmd.com<mailto:slurm-dev@schedmd.com>> Subject: [slurm-dev] Re: "Requested node configuration is not available" when using -c Josh, I believe that -n sets the number of tasks. I only want a single task, as when a single process uses multiple cores. srun -n 2 hostname returns linux-slurm2 linux-slurm3 which is definitely not what I want. Thanks, Mike On Mon, Sep 8, 2014 at 8:07 PM, Josh McSavaney <mcsa...@csh.rit.edu<mailto:mcsa...@csh.rit.edu>> wrote: I believe your slurm.conf is defining 4 nodes with a single logical processor each. You are then trying to allocate two CPUs on a single node with srun, which (according to your slurm.conf) you do not have. You may want to consider `srun -n 2 hostname` and see where that lands you. Regards, Josh McSavaney Bit Flipper Rochester Institute of Technology On Mon, Sep 8, 2014 at 7:42 PM, Christopher Samuel <sam...@unimelb.edu.au<mailto:sam...@unimelb.edu.au>> wrote: On 09/09/14 07:26, Michal Zielinski wrote: I have a small test cluster (node[1-4]) running slurm 14.03.0 setup with CR_CPU and no usage restrictions. Each node has just 1 CPU. [...] But, *srun -c 2 hostname* does not work, and it returns the above error. I have no idea why I can't dedicate 2 cores to a single job if I can dedicate each core individually to a job. What does "scontrol show node" say? cheers, Chris -- Christopher Samuel Senior Systems Administrator VLSCI - Victorian Life Sciences Computation Initiative Email: sam...@unimelb.edu.au<mailto:sam...@unimelb.edu.au> Phone: +61 (0)3 903 55545<tel:%2B61%20%280%293%20903%2055545> http://www.vlsci.org.au/ http://twitter.com/vlsci ------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------ Forschungszentrum Juelich GmbH 52425 Juelich Sitz der Gesellschaft: Juelich Eingetragen im Handelsregister des Amtsgerichts Dueren Nr. HR B 3498 Vorsitzender des Aufsichtsrats: MinDir Dr. Karl Eugen Huthmacher Geschaeftsfuehrung: Prof. Dr.-Ing. Wolfgang Marquardt (Vorsitzender), Karsten Beneke (stellv. Vorsitzender), Prof. Dr.-Ing. Harald Bolt, Prof. Dr. Sebastian M. Schmidt ------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------
