# What's New

## Index

- SLURM Version 0.6, September 2005
- SLURM Version 1.0, January 2006
- SLURM Version 1.1, May 2006
- SLURM Version 1.2, late 2006
- SLURM Version 1.3 and beyond

## Major Updates in SLURM Version 0.6

SLURM Version 0.6 became available in September 2005. Major enhancements include:

- Support for Infiniband
- Support for configurable resource limit propagation.
- MPI support moved into plugin (substantive configuration changes required for MPICH-GM).
- Srun options can be specified in job script (#SLURM ...)
- Names (not just numbers) for job step identification.

## Major Updates in SLURM Version 1.0

SLURM Version 1.0 became available in January 2006. Major enhancements include:

- I/O streams for all tasks on a node are transmitted through a single socket instead of distinct sockets for each task. This improves performance and scalability.
- Task affinity for binding tasks to CPUs.
- Nodes can be in multiple partitions, providing more flexibility in managing the SLURM partitions as queues.
- Support for task communication/synchronization primitives (PMI) as required by MPICH2.
- E-mail notification option on job state changes.
- Better control over task distribution (hostfile support).
- User control of job prioritization via nice option.
- Web-based configuration tool.
- Support to preempt/resume jobs.
- Support for deferred job initiation time specification.
- Compute node job shepherd now exec'ed program, slurmstepd. This eliminates use of SysV shared memory and some problems in support of the Native Posix Thread Library.
- Several bug fixes in interface with Maui Scheduler.
- For Blue Gene systems: support for small bglblocks.

## Major Updates in SLURM Version 1.1

SLURM Version 1.1 became available in May 2006. Major enhancements include:

- Communications enhancements, validated up to 16,384 node clusters.
- File broadcast support (new sbcast command).
- Support for distinct executables and arguments by task ID (see srun --multi-prog option).
- Support for binding tasks to the memory on a processor.
- The configuration parameter HeartbeatInterval is defunct. Half the values of configuration parameters SlurmdTimeout and SlurmctldTimeout are used as the commununication frequency for the slurmctld and slurmd daemons respecitively.
- Support for PAM to control resource limits by user on each compute node used. See UsePAM configuration parameter.
- Support added for xcpu job launch.
- Add support for 1/16 midplane BlueGene blocks.
- Add support for overlapping BlueGene blocks.
- Add support for dynamic BlueGene block creation on demand.
- BlueGene node count specifications are now c-node counts rather than base partition counts.

## Major Updates in SLURM Version 1.2

We expect to make SLURM Version 1.2 available late in 2006. Major enhancements include:

- More complete support for resource management down to the core level on a node.
- Treat memory as a consumable resource on a compute node.
- Perl API to SLURM.
- Graphical User Interfaces provided.
- Added support for OS X.
- Add Kerberos credential support including credential forwarding and refresh.
- Permit batch jobs to be requeued.

## Major Updates in SLURM Version 1.3 and beyond

Detailed plans for release dates and contents of future SLURM releases have not been finalized. Anyone desiring to perform SLURM development should notify slurm-dev@lists.llnl.gov to coordinate activies. Future development plans includes:

- Permit resource allocations (jobs) to change size.
- Convert state save functions to plugins for use of various databases.

Last modified 9 June 2006