Fix for configuration of "AuthType=munge" and "AuthInfo=socket=..." with
    alternate munge socket path.
bug 2348

The initgroups()/getgrouplist() caching in slurmd is changed to not require enumeration, instead individual entries are cached when first needed. This cache is always enabled, thus the CacheGroups configuration setting has been removed. The time that each cache entry is considered valid is determined by the GroupUpdateTime configuration parameter. scontrol reconfig will purge the cache. The default value for the GroupUpdateForce configuration parameter has changed, as systems where /etc/group contains all the groups instead of some external system like NIS, LDAP are nowadays probably the exception rather than the rule.

For slurmctld, the group cache still uses enumeration, but this is needed only to take care of special situations like multiple groups with the same GID. With enumeration disabled, group caching still works otherwise. validate_groups() does a little more optional work in order to handle the case where the user p...

If a node is out of memory, then the malloc performed by slurmstepd
  periodically may fail, killing the slurmstepd and orphaning it's
  processes.
bug 2341

Backfill scheduling fix: If a job can't be started due to a "group" resource
    limit, rather than reserve resources for it when the next job ends, don't
    reserve any resources for it. The problem with the original logic is that
    if a lot of resources are reserved for such pending jobs, then jobs futher
    down the queue may defered when they really can and should be started. An
    ideal solution would track all of the TRES resources through time as jobs
    start and end, but we don't have that logic in the backfill scheduler and
    don't want that extra overhead in the backfill scheduler.
bugs 2326 and 2282

bug 2303

Handle unexpectedly large lines for hostlists. (Bug 2333.)

While here rework to avoid extraneous xstrcat calls by using
xstrfmtcat instead of snprintf + xstrcat. Collapse line end into
own string for readability.

No performance or functional change, aside from removing possible
line truncation (which will silence additional Coverity warnings).

Removes a double xfree() in slurm_sprint_reservation_info().

When a reservation is created or updated, compress user provided node names
    using hostlist functions (e.g. translate user input of "Nodes=tux1,tux2"
    into "Nodes=tux[1-2]").
bug 2333

Match behavior of other PBS-like resource managers. Bug 2330.

Don't allow user specified reservation names to disrupt the normal
    reservation sequeuece numbering scheme.
bug 2318

anything.  The slurmd will process things correctly after the fact.

The restriction from Cray has been lifted.
bug 2317

Otherwise upgrading slurm on a compute node while tasks are running
will cause plugin mismatch, as slurmstepd would not load the library
until task completion before. Bug 2319.

Bug 2228

The restriction from Cray has been lifted.
bug 2317

Update NEWS file for final removal of Sun Constellation, Elan, and
IBM Federation (switch/nrt plugin replaces). Clean up documentation
and few outstanding ifdef blocks. Unless you were defining
HAVE_SUN_CONST there are no functional changes.

Otherwise upgrading slurm on a compute node while tasks are running
will cause plugin mismatch, as slurmstepd would not load the library
until task completion before. Bug 2319.

Bug 2314.

this happens anywhere in the code but just incase it ever does, lets fix
it.

This can be caused by a core reservation on nodes which get taken
  out of the system or fail.
bug 2296

Add "features_act" field (currently active features) to the node
    information. Output of scontrol, sinfo, and sview changed accordingly.
    The field previously displayed as "Features" is now "AvailableFeatures"
    while the new field is displayed as "ActiveFeatures".

cnodes can be reserved directly since 14.11. The plugin itself
printed warnings that it would be removed circa 15.08, following
through before 16.05.

Cray: Not running the Node Health Check after every job and step is now the
    default. Configure SelectTypeParameters with the NHC and/or NHC_STEP to
    run them.

salloc/sbatch/srun did not mention this. Also reference OverTimeLimit
as another option affecting the final run time. Bug 2309.

the job starts update the cpus_per_task appropriately.

This also moves update num_tasks to after the setting of node counts on
an update.  It didn't appear to matter, but the cpus_per_task and
pn_min_cpus had to be figured out after the cpus and nodes were set but
before tasks.

Bug 2302

Add an "scontrol top <jobid>" command to re-order the priorities of a user's
    pending jobs. May be disabled with the "disable_user_top" option in the
    SchedulerParameters configuration parameter.
bug 1133

burst_buffer/cray - Improve tracking of allocated resources to handle race
    condition when reading state while buffer allocation is in progress.
Also initialize a mutex

DBD for the first time.  The corruption is only noticed at shutdown.

Bug 2293

Set job's reason to "Priority" when higher priority job in that partition
    (or reservation) can not start rather than leaving the reason set to
    "Resources".
bug 2285

The partition-specific SelectTypeParameters parameter can now be used to
    change the memory allocation tracking specification in the global
    SelectTypeParameters configuration parameter. Supported partition-specific
    values are CR_Core, CR_Core_Memory, CR_Socket and CR_Socket_Memory. If the
    global SelectTypeParameters value includes memory allocation management and
    the partition-specific value does not, then memory allocation management for
    that partition will NOT be supported (i.e. memory can be over-allocated).
    Likewise the global SelectTypeParameters might not include memory management
    while the partition-specific value does.
bug 2239

error message.