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doku:vsc3_storage [2017/06/02 11:36] – sreinwal | doku:vsc3_storage [2021/08/23 08:52] (current) – [Quotas] goldenberg | ||
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- | ~~NOTOC~~ | ||
===== VSC-3 Storage ===== | ===== VSC-3 Storage ===== | ||
- | VSC-3 provides three facilities for persisting data: the high-performance BeeGFS Parallel Filesystem | + | **The '' |
- | * **NFS**: | + | This article is about the '' |
- | * **BeeGFS (former FhGFS)**: $GLOBAL expands to / | + | |
- | * **Scratch RAM Disk** $TMPDIR </ | + | |
+ | VSC-3 provides three facilities for persisting data: the high-performance BeeGFS Parallel Filesystem (former Fraunhofer Parallel Filesystem, FhGFS), the Network File System (NFS) and a node-local ramdisk. They are accessible under: | ||
- | ==== Usage $HOME ==== | + | * **NFS**: '' |
+ | * **BeeGFS (former FhGFS)**: **Decommissioned** | ||
+ | * '' | ||
+ | * '' | ||
+ | * **Scratch RAM Disk** '' | ||
- | $HOME is the location of the user UNIX home directory. It can be accessed from login and compute nodes. $HOME can be used to hold results, settings, source code etc. - data for which high concurrent job throughput and support for large file sizes is not required. Conversely, the parallel BeeGFS filesystem (see below) should utilized to persist temporary data in compute runs. | ||
- | Backup of $HOME is user responsibility. | + | ==== Usage '' |
- | $HOME is provided from file servers with disk arrays that are exported over the network file system (NFS). Even on highly scaled storage such on VSC-3, the number of concurrent file operations | + | '' |
+ | Backup of '' | ||
- | ==== Scratch Space Usage: | + | '' |
- | The [[http:// | ||
- | < | ||
- | $ echo $GLOBAL | ||
- | / | ||
- | </ | ||
- | The directory is writeable as user and readable by the group members. It is advisable to make use of these directories in particular for jobs with heavy I/O operations. In addition it will reduce the load on the fileserver holding the $HOME directories. | ||
- | |||
- | The BeeGFS (former Fraunhofer parallel file system) is shared by all users and by all nodes. | ||
- | Single jobs producing heavy load (>> | ||
- | |||
- | Lifetime of data is limited, see table below. | ||
- | |||
- | |||
- | === Per-node Scratch Directories $SCRATCH === | ||
- | |||
- | Local scratch directories on each node are provided as a link to the BeeGFS parallel file system and can thus be viewed also via the login nodes as '''/ | ||
- | The parallel file system (and thus the performance) is identical between $SCRATCH and $GLOBAL. | ||
- | The variable '' | ||
- | < | ||
- | $ echo $SCRATCH | ||
- | /scratch | ||
- | </ | ||
- | These directories are purged after job execution. | ||
==== Usage Local Scratch RAM Disk $TMPDIR ==== | ==== Usage Local Scratch RAM Disk $TMPDIR ==== | ||
- | ' | + | '' |
< | < | ||
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</ | </ | ||
- | \\ | ||
- | ==== Comparison of scratch directories ==== | ||
- | |||
- | | || $GLOBAL | ||
- | | Recommended file size || large || large || small || | ||
- | | Lifetime | ||
- | | Size || x00 TB (for all users) | ||
- | | Scaling | ||
- | | Visibility | ||
- | | Recommended usage || large files, available temporarily after job life || large files || many small files (>1000, or many seek-operations within a file || | ||
\\ | \\ | ||
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Storage extensions can be requested through [[https:// | Storage extensions can be requested through [[https:// | ||
- | |||
- | Since 2017-06-02 quotas are enforced for the $GLOBAL filesystem. Additional information can be found [[vsc3_global_quotas|here]] | ||
==== Fair Use ==== | ==== Fair Use ==== | ||
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VSC-3 NFS and BeeGFS (former FhGFS) servers utilize RAID-6 that can sustain up to 2 disks failing concurrently. The data path is otherwise not redundant. Data loss may also occur due to failure modes including, but not limited to natural disaster, cooling failure, disk controller failure and filesystem software faults. | VSC-3 NFS and BeeGFS (former FhGFS) servers utilize RAID-6 that can sustain up to 2 disks failing concurrently. The data path is otherwise not redundant. Data loss may also occur due to failure modes including, but not limited to natural disaster, cooling failure, disk controller failure and filesystem software faults. | ||
- | User data on VSC-2 [[doku: | + | User data on VSC-3 [[doku: |