From: Rik van Riel <riel@redhat.com> To: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@suse.de>, Srikar Dronamraju <srikar@linux.vnet.ibm.com>, Ingo Molnar <mingo@kernel.org>, Andrea Arcangeli <aarcange@redhat.com>, Johannes Weiner <hannes@cmpxchg.org>, Linux-MM <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org> Subject: [PATCH,RFC] numa,sched: use group fault statistics in numa placement Date: Thu, 1 Aug 2013 02:23:19 -0400 [thread overview] Message-ID: <20130801022319.4a6a977a@annuminas.surriel.com> (raw) In-Reply-To: <20130730113857.GR3008@twins.programming.kicks-ass.net> Subject: [PATCH,RFC] numa,sched: use group fault statistics in numa placement Here is a quick strawman on how the group fault stuff could be used to help pick the best node for a task. This is likely to be quite suboptimal and in need of tweaking. My main goal is to get this to Peter & Mel before it's breakfast time on their side of the Atlantic... This goes on top of "sched, numa: Use {cpu, pid} to create task groups for shared faults" Enjoy :) Signed-off-by: Rik van Riel <riel@redhat.com> --- kernel/sched/fair.c | 32 +++++++++++++++++++++++++++++--- 1 file changed, 29 insertions(+), 3 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6a06bef..fb2e229 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1135,8 +1135,9 @@ struct numa_group { static void task_numa_placement(struct task_struct *p) { - int seq, nid, max_nid = -1; - unsigned long max_faults = 0; + int seq, nid, max_nid = -1, max_group_nid = -1; + unsigned long max_faults = 0, max_group_faults = 0; + unsigned long total_faults = 0, total_group_faults = 0; seq = ACCESS_ONCE(p->mm->numa_scan_seq); if (p->numa_scan_seq == seq) @@ -1148,7 +1149,7 @@ static void task_numa_placement(struct task_struct *p) /* Find the node with the highest number of faults */ for (nid = 0; nid < nr_node_ids; nid++) { - unsigned long faults = 0; + unsigned long faults = 0, group_faults = 0; int priv, i; for (priv = 0; priv < 2; priv++) { @@ -1169,6 +1170,7 @@ static void task_numa_placement(struct task_struct *p) if (p->numa_group) { /* safe because we can only change our own group */ atomic_long_add(diff, &p->numa_group->faults[i]); + group_faults += atomic_long_read(&p->numa_group->faults[i]); } } @@ -1176,11 +1178,35 @@ static void task_numa_placement(struct task_struct *p) max_faults = faults; max_nid = nid; } + + if (group_faults > max_group_faults) { + max_group_faults = group_faults; + max_group_nid = nid; + } + + total_faults += faults; + total_group_faults += group_faults; } if (sched_feat(NUMA_INTERLEAVE)) task_numa_mempol(p, max_faults); + /* + * Should we stay on our own, or move in with the group? + * The absolute count of faults may not be useful, but comparing + * the fraction of accesses in each top node may give us a hint + * where to start looking for a migration target. + * + * max_group_faults max_faults + * ------------------ > ------------ + * total_group_faults total_faults + */ + if (max_group_nid >= 0 && max_group_nid != max_nid) { + if (max_group_faults * total_faults > + max_faults * total_group_faults) + max_nid = max_group_nid; + } + /* Preferred node as the node with the most faults */ if (max_faults && max_nid != p->numa_preferred_nid) {
WARNING: multiple messages have this Message-ID (diff)
From: Rik van Riel <riel@redhat.com> To: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@suse.de>, Srikar Dronamraju <srikar@linux.vnet.ibm.com>, Ingo Molnar <mingo@kernel.org>, Andrea Arcangeli <aarcange@redhat.com>, Johannes Weiner <hannes@cmpxchg.org>, Linux-MM <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org> Subject: [PATCH,RFC] numa,sched: use group fault statistics in numa placement Date: Thu, 1 Aug 2013 02:23:19 -0400 [thread overview] Message-ID: <20130801022319.4a6a977a@annuminas.surriel.com> (raw) In-Reply-To: <20130730113857.GR3008@twins.programming.kicks-ass.net> Subject: [PATCH,RFC] numa,sched: use group fault statistics in numa placement Here is a quick strawman on how the group fault stuff could be used to help pick the best node for a task. This is likely to be quite suboptimal and in need of tweaking. My main goal is to get this to Peter & Mel before it's breakfast time on their side of the Atlantic... This goes on top of "sched, numa: Use {cpu, pid} to create task groups for shared faults" Enjoy :) Signed-off-by: Rik van Riel <riel@redhat.com> --- kernel/sched/fair.c | 32 +++++++++++++++++++++++++++++--- 1 file changed, 29 insertions(+), 3 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6a06bef..fb2e229 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1135,8 +1135,9 @@ struct numa_group { static void task_numa_placement(struct task_struct *p) { - int seq, nid, max_nid = -1; - unsigned long max_faults = 0; + int seq, nid, max_nid = -1, max_group_nid = -1; + unsigned long max_faults = 0, max_group_faults = 0; + unsigned long total_faults = 0, total_group_faults = 0; seq = ACCESS_ONCE(p->mm->numa_scan_seq); if (p->numa_scan_seq == seq) @@ -1148,7 +1149,7 @@ static void task_numa_placement(struct task_struct *p) /* Find the node with the highest number of faults */ for (nid = 0; nid < nr_node_ids; nid++) { - unsigned long faults = 0; + unsigned long faults = 0, group_faults = 0; int priv, i; for (priv = 0; priv < 2; priv++) { @@ -1169,6 +1170,7 @@ static void task_numa_placement(struct task_struct *p) if (p->numa_group) { /* safe because we can only change our own group */ atomic_long_add(diff, &p->numa_group->faults[i]); + group_faults += atomic_long_read(&p->numa_group->faults[i]); } } @@ -1176,11 +1178,35 @@ static void task_numa_placement(struct task_struct *p) max_faults = faults; max_nid = nid; } + + if (group_faults > max_group_faults) { + max_group_faults = group_faults; + max_group_nid = nid; + } + + total_faults += faults; + total_group_faults += group_faults; } if (sched_feat(NUMA_INTERLEAVE)) task_numa_mempol(p, max_faults); + /* + * Should we stay on our own, or move in with the group? + * The absolute count of faults may not be useful, but comparing + * the fraction of accesses in each top node may give us a hint + * where to start looking for a migration target. + * + * max_group_faults max_faults + * ------------------ > ------------ + * total_group_faults total_faults + */ + if (max_group_nid >= 0 && max_group_nid != max_nid) { + if (max_group_faults * total_faults > + max_faults * total_group_faults) + max_nid = max_group_nid; + } + /* Preferred node as the node with the most faults */ if (max_faults && max_nid != p->numa_preferred_nid) { -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2013-08-01 6:24 UTC|newest] Thread overview: 200+ messages / expand[flat|nested] mbox.gz Atom feed top 2013-07-15 15:20 [PATCH 0/18] Basic scheduler support for automatic NUMA balancing V5 Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 01/18] mm: numa: Document automatic NUMA balancing sysctls Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 02/18] sched: Track NUMA hinting faults on per-node basis Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-17 10:50 ` Peter Zijlstra 2013-07-17 10:50 ` Peter Zijlstra 2013-07-31 7:54 ` Mel Gorman 2013-07-31 7:54 ` Mel Gorman 2013-07-29 10:10 ` Peter Zijlstra 2013-07-29 10:10 ` Peter Zijlstra 2013-07-31 7:54 ` Mel Gorman 2013-07-31 7:54 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 03/18] mm: numa: Account for THP numa hinting faults on the correct node Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-17 0:33 ` Hillf Danton 2013-07-17 0:33 ` Hillf Danton 2013-07-17 1:26 ` Wanpeng Li 2013-07-17 1:26 ` Wanpeng Li 2013-07-15 15:20 ` [PATCH 04/18] mm: numa: Do not migrate or account for hinting faults on the zero page Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-17 11:00 ` Peter Zijlstra 2013-07-17 11:00 ` Peter Zijlstra 2013-07-31 8:11 ` Mel Gorman 2013-07-31 8:11 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 05/18] sched: Select a preferred node with the most numa hinting faults Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 06/18] sched: Update NUMA hinting faults once per scan Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 07/18] sched: Favour moving tasks towards the preferred node Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-25 10:40 ` [PATCH] sched, numa: migrates_degrades_locality() Peter Zijlstra 2013-07-25 10:40 ` Peter Zijlstra 2013-07-31 8:44 ` Mel Gorman 2013-07-31 8:44 ` Mel Gorman 2013-07-31 8:50 ` Peter Zijlstra 2013-07-31 8:50 ` Peter Zijlstra 2013-07-15 15:20 ` [PATCH 08/18] sched: Reschedule task on preferred NUMA node once selected Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-17 1:31 ` Hillf Danton 2013-07-17 1:31 ` Hillf Danton 2013-07-31 9:07 ` Mel Gorman 2013-07-31 9:07 ` Mel Gorman 2013-07-31 9:38 ` Srikar Dronamraju 2013-07-31 9:38 ` Srikar Dronamraju 2013-08-01 4:47 ` Srikar Dronamraju 2013-08-01 4:47 ` Srikar Dronamraju 2013-08-01 15:38 ` Mel Gorman 2013-08-01 15:38 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 09/18] sched: Add infrastructure for split shared/private accounting of NUMA hinting faults Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-17 2:17 ` Hillf Danton 2013-07-17 2:17 ` Hillf Danton 2013-07-31 9:08 ` Mel Gorman 2013-07-31 9:08 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 10/18] sched: Increase NUMA PTE scanning when a new preferred node is selected Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 11/18] sched: Check current->mm before allocating NUMA faults Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 12/18] sched: Set the scan rate proportional to the size of the task being scanned Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 13/18] mm: numa: Scan pages with elevated page_mapcount Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-17 5:22 ` Sam Ben 2013-07-17 5:22 ` Sam Ben 2013-07-31 9:13 ` Mel Gorman 2013-07-31 9:13 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 14/18] sched: Remove check that skips small VMAs Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 15/18] sched: Set preferred NUMA node based on number of private faults Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-18 1:53 ` [PATCH 15/18] fix compilation with !CONFIG_NUMA_BALANCING Rik van Riel 2013-07-18 1:53 ` Rik van Riel 2013-07-31 9:19 ` Mel Gorman 2013-07-31 9:19 ` Mel Gorman 2013-07-26 11:20 ` [PATCH 15/18] sched: Set preferred NUMA node based on number of private faults Peter Zijlstra 2013-07-26 11:20 ` Peter Zijlstra 2013-07-31 9:29 ` Mel Gorman 2013-07-31 9:29 ` Mel Gorman 2013-07-31 9:34 ` Peter Zijlstra 2013-07-31 9:34 ` Peter Zijlstra 2013-07-31 10:10 ` Mel Gorman 2013-07-31 10:10 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 16/18] sched: Avoid overloading CPUs on a preferred NUMA node Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 20:03 ` Peter Zijlstra 2013-07-15 20:03 ` Peter Zijlstra 2013-07-16 8:23 ` Mel Gorman 2013-07-16 8:23 ` Mel Gorman 2013-07-16 10:35 ` Peter Zijlstra 2013-07-16 10:35 ` Peter Zijlstra 2013-07-16 15:55 ` Hillf Danton 2013-07-16 15:55 ` Hillf Danton 2013-07-16 16:01 ` Mel Gorman 2013-07-16 16:01 ` Mel Gorman 2013-07-17 10:54 ` Peter Zijlstra 2013-07-17 10:54 ` Peter Zijlstra 2013-07-31 9:49 ` Mel Gorman 2013-07-31 9:49 ` Mel Gorman 2013-08-01 7:10 ` Srikar Dronamraju 2013-08-01 7:10 ` Srikar Dronamraju 2013-08-01 15:42 ` Mel Gorman 2013-08-01 15:42 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 17/18] sched: Retry migration of tasks to CPU on a preferred node Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-25 10:33 ` Peter Zijlstra 2013-07-25 10:33 ` Peter Zijlstra 2013-07-31 10:03 ` Mel Gorman 2013-07-31 10:03 ` Mel Gorman 2013-07-31 10:05 ` Peter Zijlstra 2013-07-31 10:05 ` Peter Zijlstra 2013-07-31 10:07 ` Mel Gorman 2013-07-31 10:07 ` Mel Gorman 2013-07-25 10:35 ` Peter Zijlstra 2013-07-25 10:35 ` Peter Zijlstra 2013-08-01 5:13 ` Srikar Dronamraju 2013-08-01 5:13 ` Srikar Dronamraju 2013-08-01 15:46 ` Mel Gorman 2013-08-01 15:46 ` Mel Gorman 2013-07-15 15:20 ` [PATCH 18/18] sched: Swap tasks when reschuling if a CPU on a target node is imbalanced Mel Gorman 2013-07-15 15:20 ` Mel Gorman 2013-07-15 20:11 ` Peter Zijlstra 2013-07-15 20:11 ` Peter Zijlstra 2013-07-16 9:41 ` Mel Gorman 2013-07-16 9:41 ` Mel Gorman 2013-08-01 4:59 ` Srikar Dronamraju 2013-08-01 4:59 ` Srikar Dronamraju 2013-08-01 15:48 ` Mel Gorman 2013-08-01 15:48 ` Mel Gorman 2013-07-15 20:14 ` [PATCH 0/18] Basic scheduler support for automatic NUMA balancing V5 Peter Zijlstra 2013-07-15 20:14 ` Peter Zijlstra 2013-07-16 15:10 ` Srikar Dronamraju 2013-07-16 15:10 ` Srikar Dronamraju 2013-07-25 10:36 ` Peter Zijlstra 2013-07-25 10:36 ` Peter Zijlstra 2013-07-31 10:30 ` Mel Gorman 2013-07-31 10:30 ` Mel Gorman 2013-07-31 10:48 ` Peter Zijlstra 2013-07-31 10:48 ` Peter Zijlstra 2013-07-31 11:57 ` Mel Gorman 2013-07-31 11:57 ` Mel Gorman 2013-07-31 15:30 ` Peter Zijlstra 2013-07-31 15:30 ` Peter Zijlstra 2013-07-31 16:11 ` Mel Gorman 2013-07-31 16:11 ` Mel Gorman 2013-07-31 16:39 ` Peter Zijlstra 2013-07-31 16:39 ` Peter Zijlstra 2013-08-01 15:51 ` Mel Gorman 2013-08-01 15:51 ` Mel Gorman 2013-07-25 10:38 ` [PATCH] mm, numa: Sanitize task_numa_fault() callsites Peter Zijlstra 2013-07-25 10:38 ` Peter Zijlstra 2013-07-31 11:25 ` Mel Gorman 2013-07-31 11:25 ` Mel Gorman 2013-07-25 10:41 ` [PATCH] sched, numa: Improve scanner Peter Zijlstra 2013-07-25 10:41 ` Peter Zijlstra 2013-07-25 10:46 ` [PATCH] mm, sched, numa: Create a per-task MPOL_INTERLEAVE policy Peter Zijlstra 2013-07-25 10:46 ` Peter Zijlstra 2013-07-26 9:55 ` Peter Zijlstra 2013-07-26 9:55 ` Peter Zijlstra 2013-08-26 16:10 ` Peter Zijlstra 2013-08-26 16:10 ` Peter Zijlstra 2013-08-26 16:14 ` Peter Zijlstra 2013-08-26 16:14 ` Peter Zijlstra 2013-07-30 11:24 ` [PATCH] mm, numa: Change page last {nid,pid} into {cpu,pid} Peter Zijlstra 2013-07-30 11:24 ` Peter Zijlstra 2013-08-01 22:33 ` Rik van Riel 2013-08-01 22:33 ` Rik van Riel 2013-07-30 11:38 ` [PATCH] sched, numa: Use {cpu, pid} to create task groups for shared faults Peter Zijlstra 2013-07-30 11:38 ` Peter Zijlstra 2013-07-31 15:07 ` Peter Zijlstra 2013-07-31 15:07 ` Peter Zijlstra 2013-07-31 15:38 ` Peter Zijlstra 2013-07-31 15:38 ` Peter Zijlstra 2013-07-31 15:45 ` Don Morris 2013-07-31 15:45 ` Don Morris 2013-07-31 16:05 ` Peter Zijlstra 2013-07-31 16:05 ` Peter Zijlstra 2013-08-02 16:47 ` [PATCH -v3] " Peter Zijlstra 2013-08-02 16:47 ` Peter Zijlstra 2013-08-02 16:50 ` [PATCH] mm, numa: Do not group on RO pages Peter Zijlstra 2013-08-02 16:50 ` Peter Zijlstra 2013-08-02 19:56 ` Peter Zijlstra 2013-08-02 19:56 ` Peter Zijlstra 2013-08-05 19:36 ` [PATCH] numa,sched: use group fault statistics in numa placement Rik van Riel 2013-08-05 19:36 ` Rik van Riel 2013-08-09 13:55 ` Don Morris 2013-08-28 16:41 ` [PATCH -v3] sched, numa: Use {cpu, pid} to create task groups for shared faults Peter Zijlstra 2013-08-28 16:41 ` Peter Zijlstra 2013-08-28 17:10 ` Rik van Riel 2013-08-28 17:10 ` Rik van Riel 2013-08-01 6:23 ` Rik van Riel [this message] 2013-08-01 6:23 ` [PATCH,RFC] numa,sched: use group fault statistics in numa placement Rik van Riel 2013-08-01 10:37 ` Peter Zijlstra 2013-08-01 10:37 ` Peter Zijlstra 2013-08-01 16:35 ` Rik van Riel 2013-08-01 16:35 ` Rik van Riel 2013-08-01 22:36 ` [RFC PATCH -v2] " Rik van Riel 2013-08-01 22:36 ` Rik van Riel 2013-07-30 13:58 ` [PATCH 0/18] Basic scheduler support for automatic NUMA balancing V5 Andrew Theurer
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