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<p class="MsoNormal"><span style="font-size:11.0pt">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I am new to Slurm and I am working on setting up a cluster. I am testing out running a batch execution using an array and am seeing only one task executed in the array per node. Even if I specify in the sbatch
command that only one node should be used, it executes a single task on each of the available nodes in the partition. I was under the impression that it would continue to execute tasks until the resources on the node or for the user were at their limit. Am
I missing something or have I misinterpreted how sbatch and/or the job scheduling should work?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Here is one of the commands I have run:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">sbatch --array=0-15 --partition=htc-amd --wrap 'python3 -c "import time; print(\"working\"); time.sleep(5)"'<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">The htc-amd partition has 8 nodes and the results of this command are a single task being run on each node while the others are queued waiting for them to finish. As I mentioned before, if I specify --nodes=1
it will still execute a single task on every node in the partition. The only way I have gotten it to use on a single node was to use --nodelist, which worked but only to execute a single task and queued the rest. I have also tried specifying --ntasks and --ntasks-per-node.
It appears to reserve resources, as I can cause it to hit the QOS core/cpu limit, but it does not affect the number of tasks executed on each node.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thank you for any help you can offer!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">Jason<o:p></o:p></span></p>
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