Storage

The file systems used on MOGON are:

• NetApp’s WAFL → employed for the user homes.
• and Lustre → used for project directories on MOGON NHR and MOGON KI.

Both are parallel file systems, meaning that the data is accessible on every client.

The HOME-Directory#

The HOME directory on MOGON for each user is a link to /fshpc/home/<username> visible as /home/<username>.

The home directory is intended for small scripts, configuration files, aggregated results, etc.

On the login nodes the home directory quota can be checked with this command:

quota -s

The output that is displayed will look like this:

Disk quotas for user janedoe (uid 836052):
     Filesystem   space   quota   limit   grace   files   quota   limit   grace
    fshpc:/home     44K    100G    100G              18    200k    200k

The example shows that the user home uses $44K$ of the assigned quota of $100G$. Notice that there is not only a quota for memory but also for the number of files. If one of those quotas hits the limit, further file creation will be prohibited.

Project Directories on MOGON#

The project directory on MOGON currently resides under /lustre/project/<projectname>.

The project directories (resp. their underlying file systems) are optimized for I/O on many big files. All non-volatile data relevant to the project can be put here.

Projects requiring an extension of the default memory quota can contact the HPC team to provide a plausible argument as well as the desired figure of disk space. Depending on the current usage and validity of the request the HPC team may grant additional quotas.

If logged in on MOGON, the current project quota (frequently identical to group quota) and the occupied memory can be looked up with this Lustre command:

lfs quota -h -g <projectname> /lustre/project/<projectname>