NEWS

This file describes changes in recent versions of Slurm. It primarily
documents those changes that are of interest to users and administrators.

* Changes in Slurm 15.08.7
==========================
 -- sched/backfill: If a job can not be started within the configured
    backfill_window, set it's start time to 0 (unknown) rather than the end
    of the backfill_window.
 -- Remove the 1024-character limit on lines in batch scripts.
 -- burst_buffer/cray: Round up swap size by configured granularity.
 -- select/cray: Log repeated aeld reconnects.
 -- task/affinity: Disable core-level task binding if more CPUs required than
    available cores.
 -- Preemption/gang scheduling: If a job is suspended at slurmctld restart or
    reconfiguration time, then leave it suspended rather than resume+suspend.
 -- Don't use lower weight nodes for job allocation when topology/tree used.
 -- BGQ - If a cable goes into error state remove the under lying block on
    a dynamic system and mark the block in error on a static/overlap system.
 -- BGQ - Fix regression in 9cc4ae8add7f where blocks would be deleted on
    static/overlap systems when some hardware issue happens when restarting
    the slurmctld.
 -- Log if CLOUD node configured without a resume/suspend program or suspend
    time.
 -- MYSQL - Better locking around g_qos_count which was previously unprotected.
 -- Correct size of buffer used for jobid2str to avoid truncation.
 -- Fix allocation/distribution of tasks across multiple nodes when
    --hint=nomultithread is requested.
 -- If a reservation's nodes value is "all" then track the current nodes in the
    system, even if those nodes change.
 -- Fix formatting if using "tree" option with sreport.
 -- Make it so sreport prints out a line for non-existent TRES instead of
    error message.
 -- 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".
 -- Fix memory corruption when a new non-generic TRES is added to the
    DBD for the first time.  The corruption is only noticed at shutdown.
 -- burst_buffer/cray - Improve tracking of allocated resources to handle race
    condition when reading state while buffer allocation is in progress.
 -- If a job is submitted only with -c option and numcpus is updated before
    the job starts update the cpus_per_task appropriately.
 -- Update salloc/sbatch/srun documentation to mention time granularity.
 -- Fixed memory leak when freeing assoc_mgr_info_msg_t.
 -- Prevent possible use of empty reservation core bitmap, causing abort.
 -- Remove unneeded pack32's from qos_rec when qos_rec is NULL.
 -- Make sacctmgr print MaxJobsPerUser when adding/altering a QOS.
 -- Correct dependency formatting to print array task ids if set.
 -- Update sacctmgr help with current QOS options.
 -- Update slurmstepd to initialize authentication before task launch.
 -- burst_cray/cray: Eliminate need for dedicated nodes.
 -- If no MsgAggregationParams is set don't set the internal string to
    anything.  The slurmd will process things correctly after the fact.
 -- Fix output from api when printing job step not found.
 -- Don't allow user specified reservation names to disrupt the normal
    reservation sequeuece numbering scheme.
 -- Fix scontrol to be able to accept TRES as an option when creating
    a reservation.
 -- contrib/torque/qstat.pl - return exit code of zero even with no records
    printed for 'qstat -u'.
 -- 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]").
 -- Change output routines for scontrol show partition/reservation to handle
    unexpectedly large strings.
 -- Add more partition fields to "scontrol write config" output file.
 -- 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.
 -- Avoid slurmstepd abort if malloc fails during accounting gather operation.
 -- Fix nodes from being overallocated when allocation straddles multiple nodes.
 -- Fix memory leak in slurmctld job array logic.
 -- Prevent decrementing of TRESRunMins when AccountingStorageEnforce=limits is
    not set.
 -- Fix backfill scheduling bug which could postpone the scheduling of jobs due
    to avoidance of nodes in COMPLETING state.

* Changes in Slurm 15.08.6
==========================
 -- In slurmctld log file, log duplicate job ID found by slurmd. Previously was
    being logged as prolog/epilog failure.
 -- If a job is requeued while in the process of being launch, remove it's
    job ID from slurmd's record of active jobs in order to avoid generating a
    duplicate job ID error when launched for the second time (which would
    drain the node).
 -- Cleanup messages when handling job script and environment variables in
    older directory structure formats.
 -- Prevent triggering gang scheduling within a partition if configured with
    PreemptType=partition_prio and PreemptMode=suspend,gang.
 -- Decrease parallelism in job cancel request to prevent denial of service
    when cancelling huge numbers of jobs.
 -- If all ephemeral ports are in use, try using other port numbers.
 -- Revert way lib lua is handled when doing a dlopen, fixing a regression in
    15.08.5.
 -- Set the debug level of the rmdir message in xcgroup_delete() to debug2.
 -- Fix the qstat wrapper when user is removed from the system but still
    has running jobs.
 -- Log the request to terminate a job at info level if DebugFlags includes
    the Steps keyword.
 -- Fix potential memory corruption in _slurm_rpc_epilog_complete as well as
    _slurm_rpc_complete_job_allocation.
 -- Fix cosmetic display of AccountingStorageEnforce option "nosteps" when
    in use.
 -- If a job can never be started due to unsatisfied job dependencies, report
    the full original job dependency specification rather than the dependencies
    remaining to be satisfied (typically NULL).
 -- Refactor logic to synchronize active batch jobs and their script/environment
    files, reducing overhead dramatically for large numbers of active jobs.
 -- Avoid hard-link/copy of script/environment files for job arrays. Use the
    master job record file for all tasks of the job array.
    NOTE: Job arrays submitted to Slurm version 15.08.6 or later will fail if
    the slurmctld daemon is downgraded to an earlier version of Slurm.
 -- Move slurmctld mail handler to separate thread for improved performance.
 -- Fix containment of adopted processes from pam_slurm_adopt.
 -- If a pending job array has multiple reasons for being in a pending state,
    then print all reasons in a comma separated list.

* Changes in Slurm 15.08.5
==========================
 -- Prevent "scontrol update job" from updating jobs that have already finished.
 -- Show requested TRES in "squeue -O tres" when job is pending.
 -- Backfill scheduler: Test association and QOS node limits before reserving
    resources for pending job.
 -- burst_buffer/cray: If teardown operations fails, sleep and retry.
 -- Clean up the external pids when using the PrologFlags=Contain feature
    and the job finishes.
 -- burst_buffer/cray: Support file staging when job lacks job-specific buffer
    (i.e. only persistent burst buffers).
 -- Added srun option of --bcast to copy executable file to compute nodes.
 -- Fix for advanced reservation of burst buffer space.
 -- BurstBuffer/cray: Add logic to terminate dw_wlm_cli child processes at
    shutdown.
 -- If job can't be launch or requeued, then terminate it.
 -- BurstBuffer/cray: Enable clearing of burst buffer string on completed job
    as a means of recovering from a failure mode.
 -- Fix wrong memory free when parsing SrunPortRange=0-0 configuration.
 -- BurstBuffer/cray: Fix job record purging if cancelled from pending state.
 -- BGQ - Handle database throw correctly when syncing users on blocks.
 -- MySQL - Make sure we don't have a NULL string returned when not
    requesting any specific association.
 -- sched/backfill: If max_rpc_cnt is configured and the backlog of RPCs has
    not cleared after yielding locks, then continue to sleep.
 -- Preserve the job dependency description displayed in 'scontrol show job'
    even if the dependee jobs was terminated and cleaned causing the
    dependent to never run because of DependencyNeverSatisfied.
 -- Correct job task count calculation if only node count and ntasks-per-node
    options supplied.
 -- Make sure the association manager converts any string to be lower case
    as all the associations from the database will be lower case.
 -- Sanity check for xcgroup_delete() to verify incoming parameter is valid.
 -- Fix formatting for sacct with variables that switched from uint32_t to
    uint64_t.
 -- Fix a typo in sacct man page.
 -- Set up extern step to track any childern of an ssh if it leaves anything
    else behind.
 -- Prevent slurmdbd divide by zero if no associations defined at rollup time.
 -- Multifactor - Add sanity check to make sure pending jobs are handled
    correctly when PriorityFlags=CALCULATE_RUNNING is set.
 -- Add slurmdb_find_tres_count_in_string() to slurm db perl api.
 -- Make lua dlopen() conditional on version found at build.
 -- sched/backfill - Delay backfill scheduler for completing jobs only if
    CompleteWait configuration parameter is set (make code match documentation).
 -- Release a job's allocated licenses only after epilog runs on all nodes
    rather than at start of termination process.
 -- Cray job NHC delayed until after burst buffer released and epilog completes
    on all allocated nodes.
 -- Fix abort of srun if using PrologFlags=NoHold
 -- Let devices step_extern cgroup inherit attributes of job cgroup.
 -- Add new hook to Task plugin to be able to put adopted processes in the
    step_extern cgroups.
 -- Fix AllowUsers documentation in burst_buffer.conf man page. Usernames are
    comma separated, not colon delimited.
 -- Fix issue with time limit not being set correctly from a QOS when a job
    requests no time limit.
 -- Various CLANG fixes.
 -- In both sched/basic and backfill: If a job can not be started due to some
    account/qos limit, then don't start other jobs which could delay jobs. The
    old logic would skip the job and start other jobs, which could delay the
    higher priority job.
 -- select/cray: Prevent NHC from running more than once per job or step.
 -- Fix fields not properly printed when adding an account through sacctmgr.
 -- Update LBNL Node Health Check (NHC) link on FAQ.
 -- Fix multifactor plugin to prevent slurmctld from getting segmentation fault
    should the tres_alloc_cnt be NULL.
 -- sbatch/salloc - Move nodelist logic before the time min_nodes is used
    so we can set it correctly before tasks are set.

* Changes in Slurm 15.08.4
==========================
 -- Fix typo for the "devices" cgroup subsystem in pam_slurm_adopt.c
 -- Fix TRES_MAX flag to work correctly.
 -- Improve the systemd startup files.
 -- Added burst_buffer.conf flag parameter of "TeardownFailure" which will
    teardown and remove a burst buffer after failed stage-in or stage-out.
    By default, the buffer will be preserved for analysis and manual teardown.
 -- Prevent a core dump in srun if the signal handler runs during the job
    allocation causing the step context to be NULL.
 -- Don't fail job if multiple prolog operations in progress at slurmctld
    restart time.
 -- Burst_buffer/cray: Fix to purge terminated jobs with burst buffer errors.
 -- Burst_buffer/cray: Don't stall scheduling of other jobs while a stage-in