SLURM is a job-scheduler for Linux. It is most useful if you have a cluster of computers. But if you only have two or three computers it can be put to good use. SLURM is an acronym for Simple Linux Utility for Resource Management.
SLURM is used by Sunway TaihuLight with 10,649,600 computing cores, Tianhe-2 with 3,120,000 Intel Xeon E5 2.2 GHz cores (not CPUs) — Tianhe-2 is in effect a combination of 16,000 computer nodes. These two chinese machines are the two most powerful supercomputers in the world. TaihuLight is located in Wuxi, Tianhe-2 is located in Guangzhou, China. Europe’s fastest supercomputer Piz Daint uses SLURM, so does the fastest supercomputer in the middle-east, KAUST. SLURM is also used by Odyssey supercomputer at Harvard with 2,140 nodes equipped with AMD Opteron 6376 CPUs. Frankfurt’s supercomputer with 862 compute nodes, each equipped with AMD Opteron 6172 processors, also uses SLURM. Many other HPC sites as listed in Top500 use SLURM.
What is the catch of a job-scheduler? While a single operating system, like Linux, can manage jobs on a single machine, the SLURM job-scheduler can shuffle jobs around lots of machines, thereby even out the load on all of them.
Installing the software is pretty simple as it is part of Ubuntu, Debian, and many other distros.
apt-get install munge apt-get install slurm-llnl
These packages also add the users
munge goes like this:
This command creates
/etc/munge/munge.key, which is readable by the user munge only. This file is copied to all machines to the same place, i.e.,
/etc/munge/munge.key. Once this cryptographic key is created for munge, one can start the munge daemon
munged and test whether it works:
klm@chieftec:~$ echo Hello, world | munge | unmunge STATUS: Success (0) ENCODE_HOST: chieftec (127.0.1.1) ENCODE_TIME: 2014-11-07 22:37:30 +0100 (1415396250) DECODE_TIME: 2014-11-07 22:37:30 +0100 (1415396250) TTL: 300 CIPHER: aes128 (4) MAC: sha1 (3) ZIP: none (0) UID: klm (1000) GID: klm (1000) LENGTH: 13 Hello, world
It is important to use one unique
/etc/munge/munge.key file on all machines, and not to use
create-munge-key on each machine.
munged daemon is started by
munged is up and running one configures SLURM by editing
ControlMachine=nuc AuthType=auth/munge CacheGroups=0 CryptoType=crypto/munge JobCheckpointDir=/var/lib/slurm-llnl/checkpoint MpiDefault=none ProctrackType=proctrack/pgid ReturnToService=2 SlurmctldPidFile=/var/run/slurm-llnl/slurmctld.pid SlurmctldPort=6817 SlurmdPidFile=/var/run/slurm-llnl/slurmd.pid SlurmdPort=6818 SlurmdSpoolDir=/var/lib/slurm-llnl/slurmd SlurmUser=slurm StateSaveLocation=/var/lib/slurm-llnl/slurmctld SwitchType=switch/none TaskPlugin=task/none InactiveLimit=0 KillWait=30 MinJobAge=300 SlurmctldTimeout=120 SlurmdTimeout=300 Waittime=0 FastSchedule=1 SchedulerType=sched/backfill SchedulerPort=7321 SelectType=select/linear AccountingStorageLoc=/var/log/slurm-llnl/slurm_jobacct.log AccountingStorageType=accounting_storage/filetxt AccountingStoreJobComment=YES ClusterName=cluster JobCompLoc=/var/log/slurm-llnl/slurm_jobcomp.log JobCompType=jobcomp/filetxt JobAcctGatherFrequency=30 JobAcctGatherType=jobacct_gather/none SlurmctldDebug=3 SlurmctldLogFile=/var/log/slurm-llnl/slurmctld.log SlurmdDebug=3 SlurmdLogFile=/var/log/slurm-llnl/slurmd.log NodeName=chieftec CPUs=8 State=UNKNOWN NodeName=nuc CPUs=4 State=UNKNOWN PartitionName=p1 Nodes=chieftec,nuc Default=YES MaxTime=INFINITE State=UP
Starting the SLURM daemons is
As a test run
Added 05-Apr-2017: Quote from Quick Start Administrator Guide:
1. Make sure the clocks, users and groups (UIDs and GIDs) are synchronized across the cluster.
2. Install MUNGE for authentication. Make sure that all nodes in your cluster have the same munge.key. Make sure the MUNGE daemon, munged is started before you start the Slurm daemons.
Added 09-Dec-2017: If you compile SLURM yourself beware of these compiler flags, or see the build script in the AUR. SLURM also runs on ARM. My personal cluster contains a mixture of Intel, AMD, and ARM CPUs. Make sure to use the same SLURM version on all nodes.