RAM used by a suspended job is not released. At most it can be swapped
out (if enough swap is available).
Il 07/02/2023 13:14, Analabha Roy ha scritto:
Hi Sean,
Thanks for your awesome suggestion! I'm going through the reservation
docs now. At first glance, it seems like a daily reservation would turn
down jobs that are too big for the reservation. It'd be nice if
slurm could suspend (in the manner of 'scontrol suspend') jobs during
reserved downtime and resume them after. That way, folks can submit
large jobs without having to worry about the downtimes. Perhaps the FLEX
option in reservations can accomplish this somehow?
I suppose that I can do it using a shell script iterator and a cron job,
but that seems like an ugly hack. I was hoping if there is a way to
config this in slurm itself?
AR
On Tue, 7 Feb 2023 at 16:06, Sean Mc Grath <smcg...@tcd.ie
<mailto:smcg...@tcd.ie>> wrote:
Hi Analabha,
Could you do something like create a daily reservation for 8 hours
that starts at 9am, or whatever times work for you like the
following untested command:
scontrol create reservation starttime=09:00:00 duration=8:00:00
nodecnt=1 flags=daily ReservationName=daily
Daily option at https://slurm.schedmd.com/scontrol.html#OPT_DAILY
<https://slurm.schedmd.com/scontrol.html#OPT_DAILY>
Some more possible helpful documentation at
https://slurm.schedmd.com/reservations.html
<https://slurm.schedmd.com/reservations.html>, search for "daily".
My idea being that jobs can only run in that reservation, (that
would have to be configured separately, not sure how from the top of
my head), which is only active during the times you want the node to
be working. So the cronjob that hibernates/shuts it down will do so
when there are no jobs running. At least in theory.
Hope that helps.
Sean
---
Sean McGrath
Senior Systems Administrator, IT Services
------------------------------------------------------------------------
*From:* slurm-users <slurm-users-boun...@lists.schedmd.com
<mailto:slurm-users-boun...@lists.schedmd.com>> on behalf of
Analabha Roy <hariseldo...@gmail.com <mailto:hariseldo...@gmail.com>>
*Sent:* Tuesday 7 February 2023 10:05
*To:* Slurm User Community List <slurm-users@lists.schedmd.com
<mailto:slurm-users@lists.schedmd.com>>
*Subject:* Re: [slurm-users] [External] Hibernating a whole cluster
Hi,
Thanks. I had read the Slurm Power Saving Guide before. I believe
the configs enable slurmctld to check other nodes for idleness and
suspend/resume them. Slurmctld must run on a separate, always-on
server for this to work, right?
My issue might be a little different. I literally have only one node
that runs everything: slurmctld, slurmd, slurmdbd, everything.
This node must be set to "sudo systemctl hibernate"after business
hours, regardless of whether jobs are queued or running. The next
business day, it can be switched on manually.
systemctl hibernate is supposed to save the entire run state of the
sole node to swap and poweroff. When powered on again, it should
restore everything to its previous running state.
When the job queue is empty, this works well. I'm not sure how well
this hibernate/resume will work with running jobs and would
appreciate any suggestions or insights.
AR
On Tue, 7 Feb 2023 at 01:39, Florian Zillner <fzill...@lenovo.com
<mailto:fzill...@lenovo.com>> wrote:
Hi,
follow this guide: https://slurm.schedmd.com/power_save.html
<https://slurm.schedmd.com/power_save.html>
Create poweroff / poweron scripts and configure slurm to do the
poweroff after X minutes. Works well for us. Make sure to set an
appropriate time (ResumeTimeout) to allow the node to come back
to service.
Note that we did not achieve good power saving with suspending
the nodes, powering them off and on saves way more power. The
downside is it takes ~ 5 mins to resume (= power on) the nodes
when needed.
Cheers,
Florian
------------------------------------------------------------------------
*From:* slurm-users <slurm-users-boun...@lists.schedmd.com
<mailto:slurm-users-boun...@lists.schedmd.com>> on behalf of
Analabha Roy <hariseldo...@gmail.com
<mailto:hariseldo...@gmail.com>>
*Sent:* Monday, 6 February 2023 18:21
*To:* slurm-users@lists.schedmd.com
<mailto:slurm-users@lists.schedmd.com>
<slurm-users@lists.schedmd.com
<mailto:slurm-users@lists.schedmd.com>>
*Subject:* [External] [slurm-users] Hibernating a whole cluster
Hi,
I've just finished setup of a single node "cluster" with slurm
on ubuntu 20.04. Infrastructural limitations prevent me from
running it 24/7, and it's only powered on during business hours.
Currently, I have a cron job running that hibernates that sole
node before closing time.
The hibernation is done with standard systemd, and hibernates to
the swap partition.
I have not run any lengthy slurm jobs on it yet. Before I do,
can I get some thoughts on a couple of things?
If it hibernated when slurm still had jobs running/queued, would
they resume properly when the machine powers back on?
Note that my swap space is bigger than my RAM.
Is it necessary to perhaps setup a pre-hibernate script for
systemd to iterate scontrol to suspend all the jobs before
hibernating and resume them post-resume?
What about the wall times? I'm uessing that slurm will count the
downtime as elapsed for each job. Is there a way to config this,
or is the only alternative a post-hibernate script that
iteratively updates the wall times of the running jobs using
scontrol again?
Thanks for your attention.
Regards
AR
--
Analabha Roy
Assistant Professor
Department of Physics
<http://www.buruniv.ac.in/academics/department/physics>
The University of Burdwan <http://www.buruniv.ac.in/>
Golapbag Campus, Barddhaman 713104
West Bengal, India
Emails: dan...@utexas.edu <mailto:dan...@utexas.edu>,
a...@phys.buruniv.ac.in <mailto:a...@phys.buruniv.ac.in>,
hariseldo...@gmail.com <mailto:hariseldo...@gmail.com>
Webpage: http://www.ph.utexas.edu/~daneel/
<http://www.ph.utexas.edu/~daneel/>
--
Analabha Roy
Assistant Professor
Department of Physics
<http://www.buruniv.ac.in/academics/department/physics>
The University of Burdwan <http://www.buruniv.ac.in/>
Golapbag Campus, Barddhaman 713104
West Bengal, India
Emails: dan...@utexas.edu <mailto:dan...@utexas.edu>,
a...@phys.buruniv.ac.in <mailto:a...@phys.buruniv.ac.in>,
hariseldo...@gmail.com <mailto:hariseldo...@gmail.com>
Webpage: http://www.ph.utexas.edu/~daneel/
<http://www.ph.utexas.edu/~daneel/>
--
Diego Zuccato
DIFA - Dip. di Fisica e Astronomia
Servizi Informatici
Alma Mater Studiorum - Università di Bologna
V.le Berti-Pichat 6/2 - 40127 Bologna - Italy
tel.: +39 051 20 95786
