The new callbacks are not fleshed out, but eliminates a build error

function.

I run into a problem with slurm-2.5.1 that IDLE nodes can not be
allocated to jobs. This can be reproduced as follows:

First, submit a job with --no-kill option (I have SLURM_EXCLUSIVE set to
allocate nodes exclusively by default). Then set one of the nodes
allocated to the job(cn2) to state DOWN:

srun: error: Node failure on cn2
srun: error: Node failure on cn2
srun: error: cn2: task 0: Killed
^Csrun: interrupt (one more within 1 sec to abort)
srun: task 1: running
srun: task 0: exited abnormally
^Csrun: sending Ctrl-C to job 22605.0
srun: Job step aborted: Waiting up to 2 seconds for job step to finish.
srun: Force Terminated job step 22605.0

Then change state of the node to IDLE again. But it can not be allocated
to jobs:

srun: job 22606 queued and waiting for resources

  JOBID PARTITION     NAME     USER  ST       TIME  NODES
NODELIST(REASON)
  22606      work hostname     root  PD       0:00      1 (Resources)
  22604      work   sbatch     root   R       3:06      1 cn1

NodeName=cn2 Arch=x86_64 CoresPerSocket=8
   CPUAlloc=16 CPUErr=0 CPUTot=16 CPULoad=0.05 Features=abc
   Gres=(null)
   NodeAddr=cn2 NodeHostName=cn2
   OS=Linux RealMemory=30000 Sockets=2 Boards=1
   State=IDLE ThreadsPerCore=1 TmpDisk=0 Weight=1
   BootTime=2012-12-24T15:22:34 SlurmdStartTime=2013-01-14T11:06:32
   CurrentWatts=0 LowestJoules=0 ConsumedJoules=0

I traced and located the problem in select/cons_res. The call sequence
is:

slurmctld/node_mgr.c: update_node() =>
slurmctld/job_mgr.c: kill_running_job_by_node_name() =>
excise_node_from_job() =>
plugins/select/cons_res/select_cons_res.c: select_p_job_resized() =>
_rm_job_from_one_node() => _build_row_bitmaps() =>
common/job_resources: remove_job_from_cores()

If there are other jobs running in the partition, the partition row
bitmap will not be set correctly. In the example above, before
_build_row_bitmaps(), output of _dump_part() is:

[2013-01-19T13:24:56+08:00] part:work rows:1 pri:1
[2013-01-19T13:24:56+08:00]   row0: num_jobs 2: bitmap: 16,32-63

after setting the node down, output of _dump_part() is

[2013-01-19T13:24:56+08:00] part:work rows:1 pri:1
[2013-01-19T13:24:56+08:00]   row0: num_jobs 2: bitmap: 16,32-47

Cores of cn2 are not marked as available. Instead, cores of other nodes
are released. When another job requires the node cn2, the following log
message appears:

[2013-01-19T13:25:03+08:00] debug3: cons_res: _vns: node cn2 busy

I do not understand the design of select/cons_res well and I do not know
how to fix this. But it seems that _build_row_bitmaps() should not be
called, since the job is not removed totally, but only one of the nodes
released.

Correction to CPU allocation logic for cores without hyperthreading
Backport of
https://github.com/SchedMD/slurm/commit/1ef41ac9590e018e631eaefb31254622984b7d2d

From Chris Holmes, HP:
After several days of brainstorming and debugging, I have identified
a bug in SLURM 2.5.0rc2, related to the 'tree' topology. It was so
early in the execution of the whole SLURM machinery that it took me
some time to figure it out (say, 100 or 200 jobs showing the issue,
with more or less debugging levels increased and extra
instrumentation, with sometimes an uncertain reliability)...

For every “switch” a bitmap of nodes (seen down by the switch) is
built as the topology is discovered through 'topology.conf'.

There is code in read_config.c, executed when the SLURM control
daemon starts, that reorders the nodes (according to their hostname
by default), while the switches table (ie the bitmaps) has already
being built. To reorder the nodes means that the bitmaps of the switches become wrong.

slurm.MEM_PER_CPU, slurm.NO_VAL, etc.

About a year ago I submitted a modification that you incorporated
into SLURM 2.4, which was to allow an admin to modify a job to use
a QOS even though the user did not have access to the QOS.

However, I must have tested it without having the Accounting set
to enforce QOS's. So, if an admin modifies a job to a QOS they
don't have access to, it will be modified, but the job will result
in a state of InvalidQOS, which is reasonable, since this would
handle the case where a user has their QOS removed. A problem,
however, is that even though the scheduler won't schedule the job,
backfill still will.

One approach would be to fix backfill to be consistent with
the scheduler (which should probably occur regardless), but
my thought would be to modify the scheduler to allow the QOS
as long as it was set by an admin, since that was the intent
of the modification to begin with.

I believe it  would only take a single line to change, just
adding a check on the job_ptr->limit_set_qos, to make sure
it was set by an admin:

                if (job_ptr->qos_id) {
                        slurmdb_association_rec_t *assoc_ptr;
                        assoc_ptr = (slurmdb_association_rec_t *)job_ptr->assoc_ptr;
                        if (assoc_ptr &&
                            !bit_test(assoc_ptr->usage->valid_qos,
                                      job_ptr->qos_id) &&
                            !job_ptr->limit_set_qos) {
                                info("sched: JobId=%u has invalid QOS",
                                        job_ptr->job_id);
                                xfree(job_ptr->state_desc);
                                job_ptr->state_reason = FAIL_QOS;
                                continue;
                        } else if (job_ptr->state_reason == FAIL_QOS) {
                                xfree(job_ptr->state_desc);
                                job_ptr->state_reason = WAIT_NO_REASON;
                        }
                }

Phil

Without this change a high priority batch job may not start at submit
time. In addtion, a pending job with mutltiple partitions be cancelled
when the scheduler runs if any of it's partitions can not be used by
the job.

The original work this was based upon has been replaced with new
logic.

Without this patch, if the first listed partition lacks nodes
with required features the job would be rejected.

While this will validate job at submit time, it results in redundant
looping when scheduling jobs. Working on alternate patch now.

submission.