# Filesystem Quotas and Purging¶

## Overview¶

file system space inodes purge time
Project 1 TB 1 M -
Global HOME 40 GB 1 M -
Global common 10 GB 1 M -
Cori SCRATCH 20 TB 10 M 12 weeks

## Quotas¶

Warning

When a quota is reached writes to that filesystem may fail.

Note

If your $SCRATCH usage exceeds your quota, you will not be able to submit batch jobs until you reduce your usage. ### Current usage¶ NERSC provides a myquota command which displays applicable quotas and current usage. To see current usage for home and available scratch filesystems: nersc$ myquota


For project you can use

nersc$prjquota <project_name>  or use myquota with the full path to the directory nersc$ myquota --path=/project/projectdirs/<project_name>


For global common software you can use

nersc$cmnquota <project_name>  or use myquota with the full path to the directory nersc$ myquota --path=/global/common/software/<project_name>


### Increases¶

If you or your project needs additional space you may request it via the Disk Quota Increase Form.

## Purging¶

Some NERSC file systems are purged. This means the files not read (i.e. atime is updated) within a certain time period are automatically deleted. You can see the time period for the purged file systems at NERSC in the overview table. When a purge is done, a file named .purged_<date\> is left behind. This is a text file that holds the names of the files that have been removed. These .purged files will not be deleted by our purges to make sure a record of purging activities is retained. Touching files or other activites intended to circumvent the purge are forbidden by NERSC policy.