| Date | Mon, 07 Oct 2013 14:39:57 -0400 | From | Rik van Riel <> | Subject | Re: [PATCH 22/63] sched: Favour moving tasks towards the preferred node |
| |
On 10/07/2013 06:29 AM, Mel Gorman wrote: > This patch favours moving tasks towards NUMA node that recorded a higher > number of NUMA faults during active load balancing. Ideally this is > self-reinforcing as the longer the task runs on that node, the more faults > it should incur causing task_numa_placement to keep the task running on that > node. In reality a big weakness is that the nodes CPUs can be overloaded > and it would be more efficient to queue tasks on an idle node and migrate > to the new node. This would require additional smarts in the balancer so > for now the balancer will simply prefer to place the task on the preferred > node for a PTE scans which is controlled by the numa_balancing_settle_count > sysctl. Once the settle_count number of scans has complete the schedule > is free to place the task on an alternative node if the load is imbalanced. > > [srikar@linux.vnet.ibm.com: Fixed statistics] > [peterz@infradead.org: Tunable and use higher faults instead of preferred] > Signed-off-by: Peter Zijlstra <peterz@infradead.org> > Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
-- All rights reversed
|