From: Rik van Riel Date: Mon, 7 Oct 2013 10:29:08 +0000 (+0100) Subject: sched/numa: Do not migrate memory immediately after switching node X-Git-Tag: omap-for-v3.13/fixes-for-merge-window-take2~40^2~60 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6fe6b2d6dabf392aceb3ad3a5e859b46a04465c6;p=pandora-kernel.git sched/numa: Do not migrate memory immediately after switching node The load balancer can move tasks between nodes and does not take NUMA locality into account. With automatic NUMA balancing this may result in the tasks working set being migrated to the new node. However, as the fault buffer will still store faults from the old node the schduler may decide to reset the preferred node and migrate the task back resulting in more migrations. The ideal would be that the scheduler did not migrate tasks with a heavy memory footprint but this may result nodes being overloaded. We could also discard the fault information on task migration but this would still cause all the tasks working set to be migrated. This patch simply avoids migrating the memory for a short time after a task is migrated. Signed-off-by: Rik van Riel Signed-off-by: Mel Gorman Cc: Andrea Arcangeli Cc: Johannes Weiner Cc: Srikar Dronamraju Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1381141781-10992-31-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar --- Reading git-diff-tree failed