Job Resource Information

Slurm allows the use of flags to specify resources needed for a job. Below is a table describing some of the most common Slurm resource flags, followed by tables describing available Summit partitions and Quality of Service (QoS) options.

Slurm Resource Flags

Job scripts, the sbatch command, and the sinteractive command support many different resource requests in the form of flags. To review all options for sbatch, please visit the Slurm sbatch page. Below, we have listed some flags to consider when submitting your job script.

Type Description Flag
Allocations Specify an allocation account --account=allocation
Partitions Specify a partition (see table below) --partition=partition
Sending email Receive email at beginning or end of job completion --mail-type=type
Email address Email address to receive the email --mail-user=user
Number of nodes The number of nodes needed to run the job --nodes=nodes
Number of tasks The total number of processes needed to run the job --ntasks=processes
Tasks per node The number of processes you wish to assign to each node --ntasks-per-node=processes
Total Memory The total memory required to complete the Job.
Requesting more memory will reserve additional
cores proportional to how much memory was requested.
Units can be specified with the suffixes: K,M,G,T
Quality of service Specify a QOS (see table below) --qos=qos
Wall time The max. amount of time your job will run for --time=wall time
Job Name Name your job so you can identify it in the queue --job-name=jobname


On Summit, nodes with the same hardware configuration are grouped into partitions. You will need to specify a partition using --partition in your job script in order for your job to run on the appropriate type of node.

These are the partitions available on Summit.

Partition Description # of nodes cores/node RAM/core (GB) Billing weight Default and Max Walltime
shas Haswell (default) 380 24 4.84 1 4H, 24H
sgpu GPU-enabled 10 24 4.84 2.5 4H, 24H
smem* High-memory 5 48 42.7 6 4H, 7D
sknl Phi (KNL) 20 68 5.25 0.1 4H, 24H

*The smem partition is limited to 1 node per job. If you need more memory or cores, please contact

In addition to these partitions, Research Computing also provides specialized partitions for interactive and test jobs. Each of these partitions must be paired with their corresponding Quality of Service (see QoS options below).

Partition Description Max Nodes Max cores RAM/core (GB) Billing weight Default and Max Walltime
shas-testing* Haswell (default) 24 24 4.84 1 0.5H, 0.5H
shas-interactive Haswell (default) 1 1 4.84 1 1H, 4H
sgpu-testing GPU-enabled 1 24 4.84 2.5 0.5H, 0.5H
sknl-testing Phi (KNL) 1 24 5.25 1 0.5H, 0.5H

*The shas testing partition is limited to 24 cores total. These cores can be spread upon multiple nodes but only 24 will be available for the partition.

To run a job longer than 24 hours on the shas, sgpu, or sknl partitions, use the long QOS.

More details about each type of node can be found here.

Quality of Service

On Summit, Quality of Service or QoS is used to constrain or modify the characteristics that a job can have. For example, by selecting the testing QoS, a user can obtain higher queue priority for a job with the trade-off that the maximum allowed wall time is reduced from what would otherwise be allowed on that partition. We recommend specifying a QoS as well as a partition for every job.

The available QoS’s for Summit are:

QOS name Description Max walltime Max jobs/user Node limits Priority boost
normal* default see table above n/a 256/user 0
testing For quick turnaround when testing 30M 1 24 cores across up to 24 nodes QoS has dedicated cores
interactive For interactive jobs (command or GUI) 4H 1 1 core QoS has dedicated cores
long Longer wall times 7D n/a 22/user; 40 total 0
condo Condo purchased nodes only 7D n/a n/a Equiv. of 1 day queue wait time

*The normal QOS is the default QOS if no other is specified.

The testing and interactive QOS must be paired with a testing or interactive partition. Jobs that utilize testing and interactive QOS will fail if paired with a any other partition