What is the meaning of integral units of RAM used by a job?

closed

#1

When one launches a CryoSPARC job, there is a little panel on the web form showing what resources are going to be used by the job:

CPU  :  [0, 1]
GPU  :  [0, 1, 2]
RAM  :  [0, 1, 2]
SSD  :  True

All these are fairly self-explanatory (I think) save for the RAM one, which doesn’t make sense to me. What is the unit of measurement for the integral RAM units?

Thanks.


#2

Hi @pgoetz,

Each element in the array represents 8192 MB of RAM.


#3

Thank you. So the only mystery is that we start a job which reports

RAM : [0, 1, 2]

and several minutes later I still only see 4GB of RAM in use. I’m wondering how this RAM allocation is calculated?


#4

Hi @pgoetz,

It’s essentially a guideline for the internal scheduler- it has no guarantee or impact on the actual resources a job may use. These numbers were produced during our stress tests, and they’re set so that the scheduler doesn’t create a situation where it over-schedules a worker.