Scratch storage is a storage for temporary files on computing nodes. This storage should be used only during computations and should be freed after your job ends immediately.
We offer three types of the scratch storage
- ultra fast but small SSD disc, mounted to directory /scratch.ssd
- fast regular local disk, mounted to directory /scratch
- network volume available for all the nodes of a specific cluster, mounted to directory /scratch.shared
You must set the size and type of scratch dir during job submission! There is no default type of scratch, therefore user has to specify what type of scratch should be used.
-l select=1:ncpus=1:mem=4gb:scratch_local=10gb -l select=1:ncpus=1:mem=4gb:scratch_ssd=1gb -l select=1:ncpus=1:mem=4gb:scratch_shared=1gb
Allocated space on scratch disk is mentioned in system variable
$SCRATCHDIR, which value is like /directory/username/job_jobid, ie. /scratch.ssd/username/job_2477934.arien.ics.muni.cz. Scratch type is mentioned in system variable
$SCRATCH_TYPE and scratch ca[acoty in
Directory /scratch*/$USER is not writable (rights 555). Jobs can only write into allocated subdirectory /scratch*/$USER/job_JOBID. Please always check that your scripts are working with variable
Note: To see the system variable type