[slurm-users] can't create memory group (cgroup)

[Gennaro Oliva]

Hi Mike,

On Fri, Sep 07, 2018 at 03:53:44PM +0000, Mike Cammilleri wrote:
> I'm getting this error lately for everyone's jobs, which results in
> memory not being constrained via the cgroups plugin.
> 
> 
> slurmstepd: error: task/cgroup: unable to add task[pid=21681] to memory cg '(null)'
> slurmstepd: error: jobacct_gather/cgroup: unable to instanciate user 3691 memory cgroup
> 
> The result is that no uid_ direcotries are created under /sys/fs/cgroup/memory
> 
> 
> Here is our cgroup.conf file:
> 
> CgroupAutomount=yes
> CgroupReleaseAgentDir="/etc/cgroup"
> CgroupMountpoint=/sys/fs/cgroup
> ConstrainCores=yes
> ConstrainDevices=no
> ConstrainRAMSpace=yes
> ConstrainSwapSpace=yes
> AllowedSwapSpace=0
> 
> We are using jobacct_gather/cgroup
> # ACCOUNTING
> JobAcctGatherType=jobacct_gather/cgroup
> 
> The partition is configured like this
> PartitionName=long Nodes=marzano[05-13] PriorityTier=30 Default=NO MaxTime=5-0 State=UP OverSubscribe=FORCE:1
> 
> We are using slurm 16.05.6 on Ubuntu 14.04 LTS

Did you add "cgroup_enable=memory swapaccount=1" to the kernel command
line as suggested here:

https://slurm.schedmd.com/cgroups.html

Best regards,
-- 
Gennaro Oliva