Skip to end of banner
Go to start of banner

Pawsey Filesystems and their Usage

Skip to end of metadata
Go to start of metadata

You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 3 Next »


There are multiple filesystems mounted to each of Pawsey's supercomputers. Each of these filesystems are designed for particular use cases. This page provides a detailed description of these filesystems.

On this page:

Overview

The following filesystems are available from one or more Pawsey supercomputing systems:

  • /home - which should be used to store software configuration files that cannot be easily located elsewhere
  • /software - which should contain both Pawsey and researcher software installations and Slurm batch scripts
  • /scratch - which should contain working data in use by jobs that are actively queued and running on the supercomputer
  • /astro - which supports operational radio astronomy observatory work

These filesystems can be viewed using the df command from the login nodes:

$ df -H

Apart from /home, all are Lustre distributed filesystems.

Migration: Filesystems

While Pawsey is migrating to Setonix, there are existing filesystems still in use by Magnus, Galaxy, Zeus, Topaz and Garrawarla.

  • The existing /home filesystem, which will be replaced by the separate /home filesystem on Setonix.
  • The existing /group filesystem, which will be decommissioned and replaced by the Acacia object storage.
  • The existing /scratch filesystem, which will be replaced by the new /scratch filesystem on Setonix.
  • The existing /pawsey filesystem, which will be replaced by the new /software filesystem on Setonix.

Setonix will mount new /home and /scratch filesystems, which are different from Garrawarla and Topaz.

The existing filesystems will temporarily be mounted on the Setonix data mover nodes as /oldhome, /oldgroup, and /oldscratch.

The filesystems are different in many ways and are designed to facilitate different activities in supercomputing. The intended usage for each of them is explained below. Use outside of these purposes may cause poor performance for a particular activity as well as create detrimental impacts to other users.

Home filesystem

The home filesystem should be used to store software configuration files. It is a Networked FileSystem (NFS). Each user has a default login directory in the /home filesystem with a quota of 1 GB and 10,000 individual files.

/home/[username]

The location of the home directory can be displayed using the $HOME environment variable:

$ echo $HOME

The /home filesystem is intended to be used to store relatively small numbers of important system files such as your Linux profile and shell configuration.

Current usage of the /home filesystem can be viewed by executing the quota command:

$ quota -s

Due to its small quota limit and low performance, the /home filesystem is not suitable for launching or storing production work. Files such as software installations and Slurm batch scripts should be stored on the /software filesystem. Working data, such as job input and output, should use the /scratch file system.

Software filesystem

The software filesystem is intended for software installations and Slurm batch script templates. Each project has an associated directory, /software/projects/<project>, with a quota of 256 GB per project. (More can be allocated upon justified request.) Within the project directory, each project member has a subdirectory, /software/<projects>/<project>/<username>, with a limit of 100,000 individual files per user.

The user software location can be viewed by using the $MYSOFTWARE environment variable.

$ echo $MYSOFTWARE

The software filesystem is intended for storage of software installations and Slurm batch scripts for the lifetime of the project.

All members of a project have read and write access to the /software/projects/<project> directory, so it can be used for sharing software installations and batch script templates within a project. Your allocation of space on /software exists for the duration of the project and is not subject to any automatic purging.

Quotas are managed per project group. If any member of the project exceeds the shared project quota on /software, it will affect the whole project and will be unable to save data (you may see a 'quota exceeded' message')

/software is a Lustre file system and has a much higher throughput than /home. The quota can be queried using the following command:

Terminal 1. List project storage usage
$ pawseyAccountBalance -storage
...
Storage Information
-------------------
/software usage for project123, used = 899.54 GiB, quota = 1024.00 GiB

The software filesystem is not backed up.

Scratch filesystem

The scratch filesystem should be used for working data, which is input and output files actively used by jobs queued or running on the supercomputer.

Each project has a directory /scratch/<project> in which each project member has a subdirectory /scratch/<project>/<username>.

/scratch is a Lustre filesystem and its location is available in the environment variable $MYSCRATCH.

$ echo $MYSCRATCH

The scratch file system is not intended for long-term storage, is not backed up and is purged on a regular basis. If you wish to retain files, move them to the Acacia object storage.

Warning:

Files which have not been accessed for the purge period of 30 days will be deleted automatically and WILL BE LOST. See Filesystem Policies.

The /scratch filesystem has the highest performance of the available filesystems, and allows jobs to temporarily use large amounts of storage while running. However, to maintain high performance for all users, there are limits of 1 PB per project and 1 million files per user.

The project usage of the /scratch filesystem can be checked by using the following command, replacing [project]with your project name:

$ lfs quota –g <project> /scratch

To ensure that /scratch remains available to support jobs actively running on the system, it is critical to move files off the filesystem to a more permanent storage as workflows complete. The copy partition on Setonix can be used for these data transfer jobs.

Leaving files to be removed by the 30-day purge policy places an unnecessary load on the filesystem as the system is scanned for these files, and causes less capacity to be available for other users.


To minimise load on the filesystem, use the munlink command to delete files.

For more details, refer to Deleting large numbers of files.

Reference datasets

Reference data sets are static data required by software for calibrations or testing or as widely used input data. Reference data sets that are used by several project groups will be provided on /scratch by Pawsey to avoid multiple copies existing. These data sets will be contained in subdirectories of /scratch/references.

Examples include:

  • /scratch/references/askap 
  • /scratch/references/mwa 
  • /scratch/references/blastdb_update  

These reference datasets will be exempt from the /scratch  purge policy.

The specific bioinformatics reference datasets available are:

  • Arabidopsis thaliana
  • Blast+ database (regularly updated)
  • Human Broad bundle hg19, Broad bundle hg38, and GRCh38
  • Mouse Broad bundle mm10, NCBI MM10, UCSC GRCm38, RNA M25
  • Qiime
  • Diamond

If you would like to request addition of a new reference dataset, please email the Pawsey Helpdesk help@pawsey.org.au 

File permissions and quota

The effect of file permissions and ownership on storage quotas varies depending on which filesystem the data is located. The default behaviour can be summarised as such:

  • Files created in a user's /home are accessible only to that user.
  • Files created in a user's /software, /scratch or /astro directories are accessible only to that user and to members of the same project.

 For more detail on these filesystems refer to Filesystem Policies. The filesystem quotas are summarised in table 1:


Table 1. Pawsey filesystems: capacity, file limit and duration

FilesystemCapacity LimitFile LimitDuration
/home 1 GB per user10k files per userActive project allocation
/software 256 GB per project100k files per userActive project allocation
/scratch 1 PB per project1M files per user30 days from last modification

The default group membership for files and directories that are created in /home is the user's primary group, which is the same as their user ID. Files and directories that are created in any of the Lustre filesystems are associated by default with the user's project ID.

For the /software filesystem, Pawsey uses a file's group ownership to calculate its effect on storage quotas. To make use of the group quota for a project, files must be associated with the group corresponding to that project ID.

A user is always a member of their own primary group (which is the same as their own username) and can also be a member of more than one project. This is important to know because files created with a group associated to a username rather than a project are limited to a default quota of 1GB and there can be at most 100 of them.

If you encounter a write error, compiler error, or file transfer error on the /scratch or /software filesystems, this is likely because the files are counting against your personal group quota rather than your project's group quota.

File permissions are also important to consider. Here are the default permissions of a file named myscript.sh that was created in a user's home directory:

Terminal 2. List the default file permissions for a file created in /home
$ ls -ld myscript.sh
-rwxr-xr-x 1 username username 2 Nov 30 16:33 myscript.sh


Recall that Linux file permissions are broken down into three groups of three:

rwx

The first set of permissions determines what actions can be performed by the owner of the file. In this case username is the owner, and is allowed to read (r), write (w), and execute the file (x).

r-x

The second set of permissions determines what actions can be performed by other users who belong to the same group as the file. The group here is the primary or default group of the file's owner, which is username. Group members are allowed to read and execute.

r-x

The final set of permissions apply to all other users. While the permissions are set to read and execute, the top-level user directory ( /home/username ) is locked to just the user, so no others are able to read, write, or execute files in another user's home directory.


Now look at the difference for a file created in /software :

Terminal 3. List the default file permissions for a file created in /software
$ ls -ld swscript.sh
-rwxr-xr-x 1 username projectgroup 2 Nov 30 16:51 swscript.sh

The file permissions are the same as before, but with different group ownership: projectgroup. Other members of projectgroup will be able to read and execute this script. Similar to myscript.sh , the permissions for "all other users" are set to read and execute (r-x), but the top level group directory ( /software/projects/swgroup ) is locked to just the group so that others who are not in the group cannot access any files within it:

Terminal 4. Group ownership of a file
$ ls -ld /software/projects/projectgroup
drwxrws--- 46 root projectgroup 4096 Nov 29 09:06 /software/projects/projectgroup


Note there is a new flag in the group permissions, the SETGID flag (s). With the SETGID flag set on the directory, whenever a user creates a new file under /software/projectgroup, the group ownership is set to the same as the group owner of the directory, as opposed to setting the group ownership to the user who created it. So, in the example above, any file created under /software/projectgroup will have a group ownership of projectgroup instead of username.

The SETGID flag on your project's group directory is set when Pawsey staff first set up the new project so there's no need for users to modify this. However, there are situations where a user might accidentally modify permissions or ownership when moving files. For example, if a user moves a file from /home to /software (instead of copying it) the group ownership is not changed:

Terminal 5. Group ownership after moving a file from /home to /software
$ touch foo.txt
$ ls -ld foo.txt
-rw-r--r-- 1 username username 0 Nov 29 17:02 foo.txt
$ mv foo.txt $MYSOFTWARE
$ ls -ld $MYSOFTWARE/foo.txt
-rw-r--r-- 1 username username 0 Nov 29 17:03 /software/projects/projectgroup/username/foo.txt


In terminal 5, foo.txt was created in a directory on /home. As a result, the group ownership is set to user's group ( username ). The file was then moved it to the /software filesystem, and you can see that the original permissions and group remained. The file foo.txt will count against the user's quota instead of the project, even though it is located in /software.

The solution is to use the copy command (cp) instead of move (mv) when transferring files from /home to /software. This is because cp actually creates a new file, which inherits the SETGID flag from the top-level group directory:

Terminal 6. Group ownership after copying a file from /home to /software
$ touch bar.txt
$ ls -ld bar.txt
-rw-r--r-- 1 username username 0 Nov 29 17:05 bar.txt
$ cp bar.txt $MYSOFTWARE
$ ls -ld $MYSOFTWARE/bar.txt
-rw-r--r-- 1 username projectname 0 Nov 29 17:06 /software/projects/projectname/username/bar.txt


When transferring files between filesystems, you will see the above behaviour and require this workaround. When using cp, do not use the -a or -p flags. If you want to preserve timestamps, use cp --preserve=timestamps.

File transfer programs like WinSCP can also cause issues with permissions and groups. You should consult the documentation of your preferred transfer program. rsync users should avoid using the -a and -p flags; these flags will preserve permissions of the source files, which may conflict with the default behaviour on Pawsey systems. Some additional information about file transfer programs is at: Transferring Files in/out Pawsey Filesystems.

Pawsey provides a tool that lets you fix file and directory permissions on /software. The fix.group.permission.sh script is available in the pawseytools module, which is loaded by default. To use it, enter the script name followed by your group name. For example, if your project ID is projectgroup you would enter this:

$ fix.group.permission.sh projectgroup

Notes:

  • This script might take some time to complete.
  • It will only fix files and directories owned by the user executing the command ($USER).
  • You can only run one instance of the script at a time.

There is a manual way of doing this in your own area using the find command. Replace projectgroup with your project ID and username with your user name.

Terminal 7. Fix file and directory permissions on /software
$ find /software/projects/projectgroup/username ! -group projectgroup -exec chgrp projectgroup \{} \;
$ find /software/projects/projectgroup/username -type d ! -perm /g=s -exec chmod g+s \{} \;
Terminal 8. Fix file and directory permissions on /scratch
$ find /scratch/projectgroup/username ! -group projectgroup -exec chgrp projectgroup \{} \;
$ find /scratch/projectgroup/username -type d ! -perm /g=s -exec chmod g+s \{} \;

The extra tests for the find commands in terminal 7 and terminal 8 speed up the process for many files, by only changing files and directories that need to be changed.

Astronomy filesystem

The Astonomy Filesystem /astro is a Lustre filesystem provided for the scratch space needs of the MWA group who perform computations on the Garrawarla cluster.

It is an SGI/HPE provided cluster of nodes backed by DDN storage. The system currently contains 2 Metadata servers (MDS) with 2 Metadata targets (MDT). It has 4 Object Store servers (OSS) for storing data and they have 48 Object Store targets (OST). This gives approximately 2.7 PB of usable storage. It has a possible read and write speed of over 10GB/s and Pawsey staff have been easily getting 7-8GB/s when using only the four copyq nodes to transfer data around using dcp. The single threaded IO speed is greater than on /scratch due to the updated version of Lustre. 

The expandability of Lustre means that the filesystem can be expanded, without downtime, by adding more OSS's and OST Disk behind them in groups of 2 (for high availability).

Location

The Astronomy filesystem is mounted on all Garrawarla, Topaz and Setonix nodes and data mover nodes as /astro. The top level directory has directories for all the areas that /astro has:

Terminal 9. /astro directories
$ ls -l /astro/
total 20
drwxrws--- 36 root mwaeor     4096 Oct 28 09:52 mwaeor
drwxrws--- 12 root mwaops     4096 Sep 30 16:31 mwaops
drwxrws--- 47 root mwasci     4096 Dec 11 16:56 mwasci
drwxrwsr-x 57 root mwavcs     4096 Dec 16 16:46 mwavcs
drwxrws--- 27 root pawsey0001 4096 Dec 17 12:22 pawsey0001

The pawsey0001 directory is for Pawsey testing of the system and can be set up in different ways as needed. It will not often be used.

Quotas

At the time of writing MWA have requested that mwaeor, mwavcs, mwaops and mwasci are assigned 370 TB, 580 TB, 20 TB and 600 TB respectively.

To check the current quota use the following command:

$ lfs quota -g projectcode /astro

Usage

To check usage you can use the df command to check the entire filesystem. This command gives a breakdown by OST and a summary at the bottom.

Terminal 10. Using the df command to check usage
$ lfs df -h /astro/
UUID                       bytes        Used   Available Use% Mounted on
astrofs-MDT0000_UUID      542.1G       26.0G      479.4G   6% /astro[MDT:0]
astrofs-MDT0001_UUID      542.1G       32.7G      472.7G   7% /astro[MDT:1]
astrofs-OST0000_UUID       57.7T       26.6T       28.1T  49% /astro[OST:0]
astrofs-OST0001_UUID       57.7T       26.4T       28.4T  49% /astro[OST:1]
astrofs-OST0002_UUID       57.7T       25.9T       28.8T  48% /astro[OST:2]
astrofs-OST0003_UUID       57.7T       28.6T       26.2T  53% /astro[OST:3]
astrofs-OST0004_UUID       57.7T       26.9T       27.9T  50% /astro[OST:4]
astrofs-OST0005_UUID       57.7T       26.6T       28.2T  49% /astro[OST:5]
astrofs-OST0006_UUID       57.7T       26.3T       28.4T  49% /astro[OST:6]
astrofs-OST0007_UUID       57.7T       26.8T       28.0T  49% /astro[OST:7]
astrofs-OST0008_UUID       57.7T       26.8T       27.9T  50% /astro[OST:8]
astrofs-OST0009_UUID       57.7T       26.3T       28.5T  48% /astro[OST:9]
astrofs-OST000a_UUID       57.7T       26.6T       28.2T  49% /astro[OST:10]
astrofs-OST000b_UUID       57.7T       26.8T       28.0T  49% /astro[OST:11]
astrofs-OST000c_UUID       57.7T       25.6T       29.2T  47% /astro[OST:12]
astrofs-OST000d_UUID       57.7T       27.1T       27.6T  50% /astro[OST:13]
astrofs-OST000e_UUID       57.7T       27.0T       27.8T  50% /astro[OST:14]
astrofs-OST000f_UUID       57.7T       26.5T       28.3T  49% /astro[OST:15]
astrofs-OST0010_UUID       57.7T       37.3T       17.5T  69% /astro[OST:16]
astrofs-OST0011_UUID       57.7T       38.1T       16.7T  70% /astro[OST:17]
astrofs-OST0012_UUID       57.7T       37.5T       17.3T  69% /astro[OST:18]
astrofs-OST0013_UUID       57.7T       38.0T       16.7T  70% /astro[OST:19]
astrofs-OST0014_UUID       57.7T       38.0T       16.7T  70% /astro[OST:20]
astrofs-OST0015_UUID       57.7T       37.1T       17.6T  68% /astro[OST:21]
astrofs-OST0016_UUID       57.7T       37.1T       17.6T  68% /astro[OST:22]
astrofs-OST0017_UUID       57.7T       38.0T       16.7T  70% /astro[OST:23]
astrofs-OST0018_UUID       57.7T       37.4T       17.4T  69% /astro[OST:24]
astrofs-OST0019_UUID       57.7T       37.7T       17.1T  69% /astro[OST:25]
astrofs-OST001a_UUID       57.7T       38.3T       16.5T  70% /astro[OST:26]
astrofs-OST001b_UUID       57.7T       37.4T       17.4T  69% /astro[OST:27]
astrofs-OST001c_UUID       57.7T       37.5T       17.2T  69% /astro[OST:28]
astrofs-OST001d_UUID       57.7T       37.1T       17.7T  68% /astro[OST:29]
astrofs-OST001e_UUID       57.7T       37.8T       17.0T  70% /astro[OST:30]
astrofs-OST001f_UUID       57.7T       37.8T       16.9T  70% /astro[OST:31]
astrofs-OST0020_UUID       57.6T       34.6T       20.2T  64% /astro[OST:32]
astrofs-OST0021_UUID       57.6T       34.3T       20.5T  63% /astro[OST:33]
astrofs-OST0022_UUID       57.6T       34.9T       19.9T  64% /astro[OST:34]
astrofs-OST0023_UUID       57.6T       33.6T       21.1T  62% /astro[OST:35]
astrofs-OST0024_UUID       57.6T       33.5T       21.2T  62% /astro[OST:36]
astrofs-OST0025_UUID       57.6T       35.0T       19.7T  64% /astro[OST:37]
astrofs-OST0026_UUID       57.6T       33.7T       21.0T  62% /astro[OST:38]
astrofs-OST0027_UUID       57.6T       34.1T       20.6T  63% /astro[OST:39]
astrofs-OST0028_UUID       57.6T       33.5T       21.2T  62% /astro[OST:40]
astrofs-OST0029_UUID       57.6T       33.6T       21.1T  62% /astro[OST:41]
astrofs-OST002a_UUID       57.6T       34.2T       20.5T  63% /astro[OST:42]
astrofs-OST002b_UUID       57.6T       33.8T       21.0T  62% /astro[OST:43]
astrofs-OST002c_UUID       57.6T       34.9T       19.8T  64% /astro[OST:44]
astrofs-OST002d_UUID       57.6T       34.1T       20.7T  63% /astro[OST:45]
astrofs-OST002e_UUID       57.6T       33.8T       20.9T  62% /astro[OST:46]
astrofs-OST002f_UUID       57.6T       34.5T       20.2T  64% /astro[OST:47]
 
filesystem_summary:         2.7P        1.5P        1.0P  60% /astro

Related pages

External links


  • No labels