This webpage (which is part of the 3.0 series) is finally helping me out. Thanks.
On 10/18/11 19:00, Lipari, Don wrote: > Matteo, > > In a nutshell, sbatch and salloc allocate resources to the job, while srun > launches parallel tasks across those resources. When invoked within a job > allocation, srun will launch parallel tasks across some or all of the > allocated resources. In that case, srun inherits by default the pertinent > options of the sbatch or salloc which it runs under. You can then (usually) > provide srun different options which will override what it receives by > default. Each invocation of srun within a job is known as a job step. > > srun can also be invoked outside of a job allocation. In that case, srun > requests resources, and when those resources are granted, launches tasks > across those resources as a single job and job step. > > There's a relatively new web page which goes into more detail regarding the > -B and --exclusive options. > > doc/html/cpu_management.shtml > > Don > >> -----Original Message----- >> From: [email protected] [mailto:owner-slurm- >> [email protected]] On Behalf Of Matteo Guglielmi >> Sent: Tuesday, October 18, 2011 4:40 AM >> To: SLURM >> Subject: [slurm-dev] sbatch, srun, salloc: what do they "say" to each >> other? >> >> Dear All, >> >> I think slurm is great but I'm still confused on how >> >> sbatch >> srun >> salloc >> >> do work "together". >> >> They seem to have pretty much the same options but >> are these options really identical or do they have >> subtle differences (program dependent)? >> >> For example, does the "--exclusive" option have a >> different effect/meaning when it is fed to "sbatch" >> rather then "srun"? >> >> Same holds for -B or other options which are exactly >> the same from the command line point of view. >> >> I understand that sbatch is used to submit a batch >> script for later execution... but what's the >> "connection" between sbatch and srun when srun is >> called within a batch script? >> >> Who does what exactly and how are they related to >> each other? >> >> Should I give the --exclusive, --mem or -B options >> directly to sbatch (outer layer) or to the srun >> command fired up within a batch script (inner layer)? >> >> How these two layers communicates? >> >> Is the outer layer (sbatch) just passing over all >> options to srun after having "prepared" something or >> not? >> >> Or should I consider srun mostly as an independent >> program? >> >> The concept of partition, job and job step is very >> clear to me... but still I miss who's taking care >> of what. >> >> I've been through the docs and man pages several >> times but I still miss the "connections" between >> sbatch and srun. >> >> Can you clarify a bit my confusion? >> >> As stupid example... -B, --exclusive options... should >> I give them to sbatch, to srun (called within a batch >> script) or to both? >> >> What's the difference If I give it only to sbatch or >> to the srun command in a batch script? >> >> Requesting a specific allocation of resources... who >> does it actually and when? Is it sbatch at the very >> same moment it is invoked or srun (later time)... or >> both of them... or none of them actually (slurm plugin)? >> >> Thanks, >> >> --matt > > . >
