What would happen to a job if its memory usage exceeds its requested size?

Users/Site Administrators
1

what would happen to a job if its memory usage exceeds its requested size?

thanks,

Sue

2

Any resource requested ( mem, cpu, gpu, sotware, arch license , custom resource) for a job will request string for the scheduler. The scheduler finds and runs the job on a resource that satisfies the request. Scheduler is a match maker : request to resource

The job will continue to run. But in the books of the PBS Pro , the memory requested by the job is Xgb.
However, if you have enabled the mom configuration $enforce mem then the job will be killed, when it exceeds the requested memory. To be on a safer side, to make sure to use what has been requested and not to be targeted by kernel OOM killer , you can opt to use Cgroups integration with PBS Pro.
[updated $restrict mem to $enforce mem which is the correct syntax ]

3

as of which version, has this function been added?
which part of pbspro 19.2.3 big book has mentioned this function?

thanks,

Sue

4

Sorry for the syntax. It is $enforce ( i have updated in the text above ) , it is $enforce mem
Chapter 3 : MoM Parameters
RG-236 , PBS Professional 19.2.3 Reference Guide

5

If you employ the cgroups hook and enable the memory and memsw subsystems, the kernel will prevent your job from exceeding the requested size. A process that tries to utilize more memory than assigned will get ENOMEM, as if the system was out of memory.