NEWS

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

* Changes in SLURM 1.4.0-pre8
=============================
 -- In order to create a new partition using the scontrol command, use
    the "create" option rather than "update" (which will only operate
    upon partitions that already exist).
 -- Added environment variable SLURM_RESTART_COUNT to batch jobs to
    indicated the count of job restarts made.
 -- Added sacctmgr command "show config".
 -- Added the scancel option --nodelist to cancel any jobs running on a
    given list of nodes.
 -- Add partition-specific DefaultTime (default time limit for jobs, 
    if not specified use MaxTime for the partition. Patch from Par
    Andersson, National Supercomputer Centre, Sweden.
 -- Add support for the scontrol command to be able change the Weight
    associated with nodes. Patch from Krishnakumar Ravi[KK] (HP).
 -- Add DebugFlag configuration option of "CPU_Bind" for detailed CPU
    binding information to be logged.
 -- Fix some significant bugs in task binding logic (possible infinite loops
    and memory corruption).
 -- Add new node state flag of NODE_STATE_MAINT indicating the node is in
    a reservation of type MAINT.
 -- Modified task/affinity plugin to automatically bind tasks to sockets,
    cores, or threads as appropriated based upon resource allocation and
    task count. User can override with srun's --cpu_bind option. 
 -- Fix bug in backfill logic for select/cons_res plugin, resulted in 
    error "cons_res:_rm_job_from_res: node_state mis-count".
 -- Add logic go bind a batch job to the resources allocated to that job.
 -- Add configuration parameter MpiParams for (future) OpenMPI port 
    management. Add resv_port_cnt and resv_ports fields to the job step 
    data structures. Add environment variable SLURM_STEP_RESV_PORTS to
    show what ports are reserved for a job step.
 -- Add support for SchedulerParameters=interval=<sec> to control the time
    interval between executions of the backfill scheduler logic.
 -- NOTE: Cold-start (without preserving state) required for upgrade from 
    version 1.4.0-pre7.

* Changes in SLURM 1.4.0-pre7
=============================
 -- Bug fix for preemption with select/cons_res when there are no idle nodes.
 -- Bug fix for use of srun options --exclusive and --cpus-per-task together
    for job step resource allocation (tracking of cpus in use was bad).
 -- Added the srun option --preserve-env to pass the current values of 
    environment variables SLURM_NNODES and SLURM_NPROCS through to the 
    executable, rather than computing them from commandline parameters.
 -- For select/cons_res or sched/gang only: Validate a job's resource 
    allocation socket and core count on each allocated node. If the node's
    configuration has been changed, then abort the job.
 -- For select/cons_res or sched/gang only: Disable updating a node's 
    processor count if FastSchedule=0. Administrators must set a valid
    processor count although the memory and disk space configuration can
    be loaded from the compute node when it starts.
 -- Add configure option "--disable-iso8601" to disable SLURM use of ISO 8601
    time format at the time of SLURM build. Default output for all commands
    is now ISO 8601 (yyyy-mm-ddThh:mm:ss).
 -- Add support for scontrol to explicity power a node up or down using the
    configured SuspendProg and ResumeProg programs.
 -- Fix book select/cons_res logic for tracking the number of allocated
    CPUs on a node when a partition's Shared value is YES or FORCE.
 -- Added configure options "--enable-cray-xt" and "--with-apbasil=PATH" for
    eventual support of Cray-XT systems.

* Changes in SLURM 1.4.0-pre6
=============================
 -- Fix job preemption when sched/gang and select/linear are configured with
    non-sharing partitions.
 -- In select/cons_res insure that required nodes have available resources.

* Changes in SLURM 1.4.0-pre5
=============================
 -- Correction in setting of SLURM_CPU_BIND environment variable.
 -- Rebuild slurmctld's job select_jobinfo->node_bitmap on restart/reconfigure
    of the daemon rather than restoring the bitmap since the nodes in a system
    can change (be added or removed).
 -- Add configuration option "--with-cpusetdir=PATH" for non-standard 
    locations.
 -- Get new multi-core data structures working on BlueGene systems.
 -- Modify PMI_Get_clique_ranks() to return an array of integers rather 
    than a char * to satisfy PMI standard. Correct logic in 
    PMI_Get_clique_size() for when srun --overcommit option is used.
 -- Fix bug in select/cons_res, allocated a job all of the processors on a 
    node when the --exclusive option is specified as a job submit option.
 -- Add NUMA cpu_bind support to the task affinity plugin. Binds tasks to
    a set of CPUs that belong NUMA locality domain with the appropriate
    --cpu-bind option (ldoms, rank_ldom, map_ldom, and mask_ldom), see
    "man srun" for more information.

* Changes in SLURM 1.4.0-pre4
=============================
 -- For task/affinity, force jobs to use a particular task binding by setting
    the TaskPluginParam configuration parameter rather than slurmd's
    SLURM_ENFORCED_CPU_BIND environment variable.
 -- Enable full preemption of jobs by partition with select/cons_res 
    (cons_res_preempt.patch from Chris Holmes, HP).
 -- Add configuration parameter DebugFlags to provide detailed logging for
    specific subsystems (steps and triggers so far).
 -- srun's --no-kill option is passed to slurmctld so that a job step is 
    killed even if the node where srun executes goes down (unless the 
    --no-kill option is used, previous termination logic would fail if 
    srun was not responding).
 -- Transfer a job step's core bitmap from the slurmctld to the slurmd
    within the job step credential.
 -- Add cpu_bind, cpu_bind_type, mem_bind and mem_bind_type to job allocation
    request and job_details structure in slurmctld. Add support to --cpu_bind
    and --mem_bind options from salloc and sbatch commands.

* Changes in SLURM 1.4.0-pre3
=============================
 -- Internal changes: CPUs per node changed from 32-bit to 16-bit size.
    Node count fields changed from 16-bit to 32-bit size in some structures.
 -- Remove select plugin functions select_p_get_extra_jobinfo(),
    select_p_step_begin() and select_p_step_fini().
 -- Remove the following slurmctld job structure fields: num_cpu_groups,
    cpus_per_node, cpu_count_reps, alloc_lps_cnt, alloc_lps, and used_lps.
    Use equivalent fields in new "select_job" structure, which is filled
    in by the select plugins.
 -- Modify mem_per_task in job step request from 16-bit to 32-bit size.
    Use new "select_job" structure for the job step's memory management.
 -- Add core_bitmap_job to slurmctld's job step structure to identify
    which specific cores are allocated to the step.
 -- Add new configuration option OverTimeLimit to permit jobs to exceed 
    their (soft) time limit by a configurable amount. Backfill scheduling
    will be based upon the soft time limit.
 -- Remove select_g_get_job_cores(). That data is now within the slurmctld's
    job structure.

* Changes in SLURM 1.4.0-pre2
=============================
 -- Remove srun's --ctrl-comm-ifhn-addr option (for PMI/MPICH2). It is no
    longer needed.
 -- Modify power save mode so that nodes can be powered off when idle. See
    https://computing.llnl.gov/linux/slurm/power_save.html or 
    "man slurm.conf" (SuspendProgram and related parameters) for more 
    information.
 -- Added configuration parameter PrologSlurmctld, which can be used to boot
    nodes into a particular state for each job. See "man slurm.conf" for 
    details.
 -- Add configuration parameter CompleteTime to control how long to wait for 
    a job's completion before allocating already released resources to pending
    jobs. This can be used to reduce fragmentation of resources. See
    "man slurm.conf" for details.
 -- Make default CryptoType=crypto/munge. OpenSSL is now completely optional.
 -- Make default AuthType=auth/munge rather than auth/none.
 -- Change output format of "sinfo -R" from "%35R %N" to "%50R %N".

* Changes in SLURM 1.4.0-pre1
=============================
 -- Save/restore a job's task_distribution option on slurmctld retart.
    NOTE: SLURM must be cold-started on converstion from version 1.3.x.
 -- Remove task_mem from job step credential (only job_mem is used now).
 -- Remove --task-mem and --job-mem options from salloc, sbatch and srun
    (use --mem-per-cpu or --mem instead).
 -- Remove DefMemPerTask from slurm.conf (use DefMemPerCPU or DefMemPerNode
    instead).
 -- Modify slurm_step_launch API call. Move launch host from function argument
    to element in the data structure slurm_step_launch_params_t, which is
    used as a function argument.
 -- Add state_reason_string to job state with optional details about why
    a job is pending.
 -- Make "scontrol show node" output match scontrol input for some fields
    ("Cores" changed to "CoresPerSocket", etc.).
 -- Add support for a new node state "FUTURE" in slurm.conf. These node records
    are created in SLURM tables for future use without a reboot of the SLURM
    daemons, but are not reported by any SLURM commands or APIs.

* Changes in SLURM 1.3.14
=========================
 -- Fix bug in squeue command with sort on job name ("-S j" option) for jobs
    that lack a name. Previously generated an invalid memory reference.
 -- Permit the TaskProlog to write to the job's standard output by writing
    a line containing the prefix "print " to it's standard output.
 -- Fix for making the slurmdbd agent thread start up correctly when 
    stopped and then started again.
 -- Prevent the Linux out of memory killer from killing the slurmd or
    slurmstepd daemons. Patch from Hongjia Cao, NUDT.
 -- Add squeue option to report jobs by account (-U or --account). Patch from
    Par Andersson, National Supercomputer Centre, Sweden.
 -- Add -DNUMA_VERSION1_COMPATIBILITY to Makefile CFLAGS for proper behavior
    when building with NUMA version 2 APIs.
 -- BLUEGENE - slurm works on a BGP system.
 -- BLUEGENE - slurm handles HTC blocks
 -- BLUEGENE - Added option DenyPassthrough in the bluegene.conf.  Can be set
    to any combination of X,Y,Z to not allow passthroughs when running in 
    dynamic layout mode.
 -- Fix bug in logic to remove a job's dependency, could result in abort.
 -- Add new error message to sched/wiki and sched/wiki2 (Maui and Moab) for
    STARTJOB request: "TASKLIST includes non-responsive nodes".
 -- Fix bug in select/linear when used with sched/gang that can result in a 
    job's required or excluded node specification being ignored.
 -- Add logic to handle message connect timeouts (timed-out.patch from 
    Chuck Clouston, Bull).
 -- Update python-hostlist code from Kent Engström (NSC) to v1.5
    - Add hostgrep utility to search for lines matching a hostlist.
    - Make each "-" on the command line count as one hostlist argument.
      If multiple hostslists are given on stdin they are combined to a
      union hostlist before being used in the way requested by the
      options.