====== Queue | Partition | QOS setup on VSC-5 ======
On VSC-5, Nodes of the same type of hardware are grouped to partitions. The quality of service (QOS), former called //Queue// defines the maximum run time of a job and the number and type of allocate-able nodes.

For submitting jobs to [[doku:slurm]], three parameters are important:

<code bash>
#SBATCH --account=xxxxxx
#SBATCH --partition=xxxxx_xxxx
#SBATCH --qos=xxxxx_xxxx
</code>

Notes:

  * Core hours will be charged to the specified account.
  * Account, partition, and qos have to fit together
  * If the account is not given, the default account will be used.
  * If partition and QOS are not given, default values are ''zen3_0512'' for both.


===== Partitions =====

Nodes of the same type of hardware are grouped to partitions, there are three basic types:
  * Intel CPU nodes: There is only one variant with Cascadelake CPUs and 368GB RAM.
  * AMD CPU nodes: They all have Zen3 CPU nodes, but come in three memory versions - 512GB, 1TB and 2TB RAM.
  * GPU nodes: there are two versions, one with Zen2 CPUs, 256GB RAM and 2x nVidia A40 GPUs, and one with Zen3 CPUs, 512GB RAM and 2x nVidia A100 GPUs.

These are the partitions on VSC-5:

^ Partition ^ Nodes ^ Architecture ^ CPU ^ Cores per CPU (physical/with HT) ^ GPU ^ RAM ^ Use ^
| zen3_0512* | 564 | AMD | 2x AMD 7713 | 64/128 | No | 512 GB | The default partition |
| zen3_1024 | 120 | AMD | 2x AMD 7713 | 64/128 | No | 1 TB | High Memory partition |
| zen3_2048 | 20 | AMD | 2x AMD 7713 | 64/128 | No | 2 TB | Higher Memory partition |
| cascadelake_0384 | 48 | Intel | 2x Intel Cascadelake | 48/96 | No | 384 GB | Directly use programs compiled for VSC-4 |
| zen2_0256_a40x2 | 45 | AMD | 2x AMD 7252 | 8/16 | 2x NVIDIA A40 | 256 GB | Best for single precision GPU code |
| zen3_0512_a100x2 | 60 | AMD | 2x AMD 7713 | 64/128 | 2x NVIDIA A100 | 512 GB | Best for double precision GPU code |

Type ''sinfo -o %P'' on any node to see all the available partitions.

For the sake of completeness there are internally used //special// partitions, that can not be selected manually:

^ Partition ^ Description ^
| login5 | login nodes, not an actual slurm partition |
| rackws5 | GUI login nodes, not an actual slurm partition |
| _jupyter | variations of zen3, a40 and a100 nodes reserved for the jupyterhub |


===== Quality of service (QOS) =====

The QOS defines the maximum run time of a job and the number and type of allocate-able nodes.

The QOSs that are assigned to a specific user can be viewed with:

<code>
sacctmgr show user `id -u` withassoc format=user,defaultaccount,account,qos%40s,defaultqos%20s
</code>

All QOS usable are also shown right after login.


==== QOS, Partitions and Run time limits ====

The following QoS are available for all normal (=non private) projects:

^ QOS name ^ Gives access to Partition ^ Hard run time limits  ^ Description ^
|zen3_0512 | zen3_0512 | 72h (3 days) | Default |
|zen3_1024 | zen3_1024 | 72h (3 days) | High Memory |
|zen3_2048 | zen3_2048 | 72h (3 days) | Higher Memory |
|cascadelake_0384 | cascadelake_0384 | 72h (3 days) |
|zen2_0256_a40x2 | zen2_0256_a40x2 | 72h (3 days) | GPU Nodes |
|zen3_0512_a100x2 | zen3_0512_a100x2 | 72h (3 days) | GPU Nodes |
|zen3_0512_devel | 5 nodes on zen3_0512 | 10min | Fast Feedback |


==== Idle QOS ====

If a project runs out of compute time, jobs of this project are now running with low job priority and reduced maximum run time limit in the //idle// QOS.

There is no //idle// QOS on ''cascadelake'' or ''zen2_0256_a40x2''/''zen3_0512_a100x2'' GPU Nodes.

^ QOS name ^ Gives access to Partition ^ Hard run time limits ^  Description ^
| idle_0512 | zen3_0512 | 24h (1 day) | Projects out of compute time | 
| idle_1024 | zen3_1024 | 24h (1 day) | Projects out of compute time | 
| idle_2048 | zen3_2048 | 24h (1 day) | Projects out of compute time | 


==== Devel QOS ====

The //devel// QOS gives fast feedback to the user when their job is running. Connect to the node where the actual job is running to directly [[doku:monitoring|monitor]] to check if the threads/processes are doing what you expect. We recommend this before sending the job to one of the ''compute'' queues.

^ QOS name ^ Gives access to Partition ^ Hard run time limits  ^
|zen3_0512_devel | 5 nodes on zen3_0512 | 10min |

==== Private Projects ====

Private projects come with different QOS; nevertheless partition, QOS, and account have to fit together.

^ QOS name ^ Gives access to Partition ^ Hard run time limits  ^ 
| p....._0...  | various | up to 240h (10 days) | private queues |

For submitting jobs to [[doku:slurm]], three parameters are important:

<code bash>
#SBATCH --account=pxxxxx 
#SBATCH --partition=zen3_xxxx
#SBATCH --qos=pxxxx_xxxx
</code> 


==== Run time ====

The QOS's run time limits can also be requested via the command

<code>sacctmgr show qos  format=name%20s,priority,grpnodes,maxwall,description%40s</code>

If you know how long your job usually runs, you can set the run time limit in SLURM:

<code>
#SBATCH --time=<time>
</code>

 Of course this has to be //below// the default QOS's run time limit. Your job might start earlier, which is nice; But after the specified time is elapsed, the job is killed!

Acceptable time formats include:
  * "minutes"
  * "minutes:seconds"
  * "hours:minutes:seconds"
  * "days-hours"
  * "days-hours:minutes"
  * "days-hours:minutes:seconds".