How to best use scratch
From ALICE Documentation
How to best use local scratch
In general, the best way to use the local scratch file system on /scratchdata
is to copy your input files from your directory on /home
or /data
to the local scratch at the start of a job, create all temporary files needed by your job on the local scratch (assuming they don't need to be shared with other nodes) and copy all output files at the end of a job back to your /home
or /data
directory.
There are two things to note:
- On the node that your job is running on, a directory will be created for you upon the start of a job. The directory name is
/scratchdata/${SLURM_JOB_USER}/${SLURM_JOB_ID}
whereSLURM_JOB_USER
is your ALICE username andSLURM_JOB_ID
is the id of the job. You do not have to define these two variables yourself. They will be available for your to use in your job script. - Do not forget to copy your results back to
/home
or/data
! The local scratch space will be cleaned and the directory will be removed after your job finishes and your results will be lost if you forget this step.