The symptom is that SLURM schedules lower priority jobs to run when higher priority, dependent jobs have their dependencies satisfied.  This happens because dependent jobs still have a priority of 1 when the job queue is sorted in the schedule() function.  The proposed fix forces jobs to have their priority updated when their dependencies are satisfied.

The commit 8b14f388 on Jan 19, 2011 is causing problems with Moab cluster-scheduled machines.  Under this case, Moab hands off every job submitted immediately to SLURM which gets a zero priority.  Once Moab schedules the job, Moab raises the job's priority to 10,000,000 and the job runs.

When you happen to restart the slurmctld under such conditions, the sync_job_priorities() function runs which attempts to raise job priorities into a higher range if they are getting too close to zero.  The problem as I see it is that you include the "boost" for zero priority jobs.  Hence the problem we are seeing is that once the slurmctld is restarted, a bunch of zero priority jobs are suddenly eligible.  So there becomes a disconnect between the top priority job Moab is trying to start and the top priority job SLURM sees.

I believe the fix is simple:

diff job_mgr.c~ job_mgr.c
6328,6329c6328,6331
<       while ((job_ptr = (struct job_record *) list_next(job_iterator)))
<               job_ptr->priority += prio_boost;
---
       while ((job_ptr = (struct job_record *) list_next(job_iterator))) {
               if (job_ptr->priority)
                       job_ptr->priority += prio_boost;
       }
Do you agree?

Don

Here is the way to reproduce it :
[root@cuzco27 georgioy]# salloc -n64 -N4 --exclusive
salloc: Granted job allocation 8
[root@cuzco27 georgioy]#srun -r 0 -n 30 -N 2 sleep 300&
[root@cuzco27 georgioy]#srun -r 1 -n 40 -N 3 sleep 300&
[root@cuzco27 georgioy]# srun: error: slurm_receive_msg: Zero Bytes were transmitted or received
srun: error: Unable to create job step: Zero Bytes were transmitted or received

batch jobs.

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There is a minor problem with the display of partition names in
"sinfo".  Without options, the partition name field displays a
asterisk "*" at the end of the name of the Default partition.  If you
specify a formatting option which contains the %P field specifier with
a width option (e.g., sinfo -o %8P) the asterisk also is appended to
the default partition name.  With no width option, the "%P" displays
the name based on the full length of the name string, however, no "*"
is appended on the default partition name.

The attached patch for version 2.4.0-pre4 corrects the problem so that
the "*" is correctly appended when %P with no width specifier is
used. The patch will also apply to version 2.3.4.

  -Don Albert-

Previously the code would come up with how much memory a PE should have
instead of the memory a node should have.

Fix sched/wiki2 to support job account name, gres, partition name, wckey,
or working directory that contains "#" (a job record separator). Without
this patch, the parsing will probably stop once reaching the "#".

and cons_res or gang scheduling.  The slurm.conf is always used for a node
configuration in this case, and it ignores what the actual hardware is
because in this situation the slurmctld needs to make a bunch of bitmaps
before the slurmd's register.

and time limit where it was previously set by an admin.

slurmdbd accounting and running large amounts of jobs (>50 sec).  Job
information could be corrupted before it had a chance to reach the DBD.

qos.

While safeguards are in place to prevent unauthorized users from extending the
TimeLimit of their running jobs, there were no such restrictions for extending
the EndTime.  This patch adds the same constraints to modifying EndTime that
currently exists for modifying TimeLimit.

Add support for new SchedulerParameters of max_depend_depth defining the
maximum number of jobs to test for circular dependencies (i.e. job A waits
for job B to start and job B waits for job A to start). Default value is
10 jobs.

The problem was conflicting logic in the select/cons_res plugin. Some of the code was trying to get the job the maximum node count in the range while other logic was trying to minimize spreading out of the job across multiple switches. As you note, this problem only happens when a range of node counts is specified and the select/cons_res plugin and the topology/tree plugin and even then it is not easy to reproduce (you included all of the details below).

Quoting Martin.Perry@Bull.com:

> Certain combinations of topology configuration and srun -N option produce
> spurious job rejection with "Requested node configuration is not
> available" with select/cons_res. The following example illustrates the
> problem.
>
> [sulu] (slurm) etc> cat slurm.conf
> ...
> TopologyPlugin=topology/tree
> SelectType=select/cons_res
> SelectTypeParameters=CR_Core
> ...
>
> [sulu] (slurm) etc> cat topology.conf
> SwitchName=s1 Nodes=xna[13-26]
> SwitchName=s2 Nodes=xna[41-45]
> SwitchName=s3 Switches=s[1-2]
>
> [sulu] (slurm) etc> sinfo
> PARTITION AVAIL  TIMELIMIT  NODES  STATE NODELIST
> ...
> jkob         up   infinite      4   idle xna[14,19-20,41]
> ...
>
> [sulu] (slurm) etc> srun -N 2-4 -n 4 -p jkob hostname
> srun: Force Terminated job 79
> srun: error: Unable to allocate resources: Requested node configuration is
> not available
>
> The problem does not occur with select/linear, or topology/none, or if -N
> is omitted, or for certain other values for -N (for example, -N 4-4 and -N
> 2-3 work ok). The problem seems to be in function _eval_nodes_topo in
> src/plugins/select/cons_res/job_test.c. The srun man page states that when
> -N is used, "the job will be allocated as many nodes as possible within
> the range specified and without delaying the initiation of the job."
> Consistent with this description, the requested number of nodes in the
> above example is 4 (req_nodes=4).  However, the code that selects the
> best-fit topology switches appears to make the selection based on the
> minimum required number of nodes (min_nodes=2). It therefore selects
> switch s1.  s1 has only 3 nodes from partition jkob. Since this is fewer
> than req_nodes the job is rejected with the "node configuration" error.
>
> I'm not sure where the code is going wrong.  It could be in the
> calculation of the number of needed nodes in function _enough_nodes.  Or
> it could be in the code that initializes/updates req_nodes or rem_nodes. I
> don't feel confident that I understand the logic well enough to propose a
> fix without introducing a regression.
>
> Regards,
> Martin

When the optional max_time is not specified for --switches=count, the site
max (SchedulerParameters=max_switch_wait=seconds) is used for the job.
Based on patch from Rod Schultz.

Patch by Bill Brophy, Bull.

Patch by Don Lipari, LLNL.
https://github.com/chaos/slurm/commit/4de11bf0a8cd18207a60e7d3e1fa7a6fde0da431

CRAY: Fix support for configuration with SlurmdTimeout=0 (never mark
node that is DOWN in ALPS as DOWN in SLURM).

Improve support for overlapping advanced reservations.
Patch from Bill Brophy, Bull.

task/cgroup: minor job step memcg fixes