There's a new version of the node affine NUMA scheduler extension based
on the O(1) scheduler at
http://home.arcor.de/efocht/sched/Nod18_2.4.18-ia64-O1ef7.patch
The patch is for 2.4.18 kernels and it has been tested on IA64 systems.
It requires the O(1) scheduler patch with the corrected complex macros
which I posted to the LSE and linux-ia64 mailing lists last week. For
IA64 you should use:
http://home.arcor.de/efocht/sched/O1_ia64-ef7-2.4.18.patch.bz2
which should be applied to 2.4.18 + ia64-020622 patch.
For IA32 (NUMA-Q) try instead:
http://home.arcor.de/efocht/sched/O1_i386-ef7-2.4.18.patch.bz2
What is it good for?
- Extends the scheduler to NUMA.
- Each task gets a homenode assigned at start (initial load balancing).
- A memory affinity patch (like discontigmem, or similar) should take
care that the memory of the task is allocated mainly from its
homenode.
- The scheduler attracts the tasks to their homenodes while trying to
keep the nodes equally balanced.
- Target: keep processes and their memory on the same node to reduce
memory access latencies without having to fiddle with the
cpus_allowed masks (hard affinities).
- Within one node, behaves like the normal O(1) scheduler.
For an overview over the features have a look at:
http://home.arcor.de/efocht/sched
There are several changes compared to the previous version, the most
important ones are:
- Extension to multilevel NUMA hierarchy by implementing delays when
stealing tasks from remote nodes.
- Better selection of task to be stolen from busiest runqueue. Take
into account cache coolness, node and supernode of task and runqueue.
Comments and feedback are very wellcome.
Regards,
Erich