From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
Mel Gorman <mgorman@techsingularity.net>,
Rik van Riel <riel@surriel.com>,
Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH v2 18/19] sched/numa: Reset scan rate whenever task moves across nodes
Date: Wed, 20 Jun 2018 22:32:59 +0530 [thread overview]
Message-ID: <1529514181-9842-19-git-send-email-srikar@linux.vnet.ibm.com> (raw)
In-Reply-To: <1529514181-9842-1-git-send-email-srikar@linux.vnet.ibm.com>
Currently task scan rate is reset when numa balancer migrates the task
to a different node. If numa balancer initiates a swap, reset is only
applicable to the task that initiates the swap. Similarly no scan rate
reset is done if the task is migrated across nodes by traditional load
balancer.
Instead move the scan reset to the migrate_task_rq. This ensures the
task moved out of its preferred node, either gets back to its preferred
node quickly or finds a new preferred node. Doing so, would be fair to
all tasks migrating across nodes.
Running SPECjbb2005 on a 4 node machine and comparing bops/JVM
JVMS LAST_PATCH WITH_PATCH %CHANGE
16 26251.7 25862.6 -1.48
1 74108 74357 0.335
Running SPECjbb2005 on a 16 node machine and comparing bops/JVM
JVMS LAST_PATCH WITH_PATCH %CHANGE
8 120453 117019 -2.85
1 181140 179095 -1.12
(numbers from v1 based on v4.17-rc5)
Testcase Time: Min Max Avg StdDev
numa01.sh Real: 428.48 837.17 700.45 162.77
numa01.sh Sys: 78.64 247.70 164.45 58.32
numa01.sh User: 37487.25 63728.06 54399.27 10088.13
numa02.sh Real: 60.07 62.65 61.41 0.85
numa02.sh Sys: 15.83 29.36 21.04 4.48
numa02.sh User: 5194.27 5280.60 5236.55 28.01
numa03.sh Real: 814.33 881.93 849.69 27.06
numa03.sh Sys: 111.45 134.02 125.28 7.69
numa03.sh User: 63007.36 68013.46 65590.46 2023.37
numa04.sh Real: 412.19 438.75 424.43 9.28
numa04.sh Sys: 232.97 315.77 268.98 26.98
numa04.sh User: 33997.30 35292.88 34711.66 415.78
numa05.sh Real: 394.88 449.45 424.30 22.53
numa05.sh Sys: 262.03 390.10 314.53 51.01
numa05.sh User: 33389.03 35684.40 34561.34 942.34
Testcase Time: Min Max Avg StdDev %Change
numa01.sh Real: 449.46 770.77 615.22 101.70 13.85%
numa01.sh Sys: 132.72 208.17 170.46 24.96 -3.52%
numa01.sh User: 39185.26 60290.89 50066.76 6807.84 8.653%
numa02.sh Real: 60.85 61.79 61.28 0.37 0.212%
numa02.sh Sys: 15.34 24.71 21.08 3.61 -0.18%
numa02.sh User: 5204.41 5249.85 5231.21 17.60 0.102%
numa03.sh Real: 785.50 916.97 840.77 44.98 1.060%
numa03.sh Sys: 108.08 133.60 119.43 8.82 4.898%
numa03.sh User: 61422.86 70919.75 64720.87 3310.61 1.343%
numa04.sh Real: 429.57 587.37 480.80 57.40 -11.7%
numa04.sh Sys: 240.61 321.97 290.84 33.58 -7.51%
numa04.sh User: 34597.65 40498.99 37079.48 2060.72 -6.38%
numa05.sh Real: 392.09 431.25 414.65 13.82 2.327%
numa05.sh Sys: 229.41 372.48 297.54 53.14 5.710%
numa05.sh User: 33390.86 34697.49 34222.43 556.42 0.990%
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
kernel/sched/fair.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 7350f09..36d1414 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1807,12 +1807,6 @@ static int task_numa_migrate(struct task_struct *p)
if (env.best_cpu == -1)
return -EAGAIN;
- /*
- * Reset the scan period if the task is being rescheduled on an
- * alternative node to recheck if the tasks is now properly placed.
- */
- p->numa_scan_period = task_scan_start(p);
-
best_rq = cpu_rq(env.best_cpu);
if (env.best_task == NULL) {
pg_data_t *pgdat = NODE_DATA(cpu_to_node(env.dst_cpu));
@@ -6668,6 +6662,19 @@ static void migrate_task_rq_fair(struct task_struct *p, int new_cpu __maybe_unus
/* We have migrated, no longer consider this task hot */
p->se.exec_start = 0;
+
+#ifdef CONFIG_NUMA_BALANCING
+ if (!p->mm || (p->flags & PF_EXITING))
+ return;
+
+ if (p->numa_faults) {
+ int src_nid = cpu_to_node(task_cpu(p));
+ int dst_nid = cpu_to_node(new_cpu);
+
+ if (src_nid != dst_nid)
+ p->numa_scan_period = task_scan_start(p);
+ }
+#endif
}
static void task_dead_fair(struct task_struct *p)
--
1.8.3.1
next prev parent reply other threads:[~2018-06-20 17:04 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-20 17:02 [PATCH v2 00/19] Fixes for sched/numa_balancing Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 01/19] sched/numa: Remove redundant field Srikar Dronamraju
2018-07-25 14:23 ` [tip:sched/core] " tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 02/19] sched/numa: Evaluate move once per node Srikar Dronamraju
2018-06-21 9:06 ` Mel Gorman
2018-07-25 14:24 ` [tip:sched/core] " tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 03/19] sched/numa: Simplify load_too_imbalanced Srikar Dronamraju
2018-07-25 14:24 ` [tip:sched/core] sched/numa: Simplify load_too_imbalanced() tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 04/19] sched/numa: Set preferred_node based on best_cpu Srikar Dronamraju
2018-06-21 9:17 ` Mel Gorman
2018-07-25 14:25 ` [tip:sched/core] " tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 05/19] sched/numa: Use task faults only if numa_group is not yet setup Srikar Dronamraju
2018-06-21 9:38 ` Mel Gorman
2018-07-25 14:25 ` [tip:sched/core] sched/numa: Use task faults only if numa_group is not yet set up tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 06/19] sched/debug: Reverse the order of printing faults Srikar Dronamraju
2018-07-25 14:26 ` [tip:sched/core] " tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 07/19] sched/numa: Skip nodes that are at hoplimit Srikar Dronamraju
2018-07-25 14:27 ` [tip:sched/core] sched/numa: Skip nodes that are at 'hoplimit' tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 08/19] sched/numa: Remove unused task_capacity from numa_stats Srikar Dronamraju
2018-07-25 14:27 ` [tip:sched/core] sched/numa: Remove unused task_capacity from 'struct numa_stats' tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 09/19] sched/numa: Modify migrate_swap to accept additional params Srikar Dronamraju
2018-07-25 14:28 ` [tip:sched/core] sched/numa: Modify migrate_swap() to accept additional parameters tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 10/19] sched/numa: Stop multiple tasks from moving to the cpu at the same time Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 11/19] sched/numa: Restrict migrating in parallel to the same node Srikar Dronamraju
2018-07-23 10:38 ` Peter Zijlstra
2018-07-23 11:16 ` Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 12/19] sched/numa: Remove numa_has_capacity Srikar Dronamraju
2018-07-25 14:28 ` [tip:sched/core] sched/numa: Remove numa_has_capacity() tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 13/19] mm/migrate: Use xchg instead of spinlock Srikar Dronamraju
2018-06-21 9:51 ` Mel Gorman
2018-07-23 10:54 ` Peter Zijlstra
2018-07-23 11:20 ` Srikar Dronamraju
2018-07-23 14:04 ` Peter Zijlstra
2018-06-20 17:02 ` [PATCH v2 14/19] sched/numa: Updation of scan period need not be in lock Srikar Dronamraju
2018-06-21 9:51 ` Mel Gorman
2018-07-25 14:29 ` [tip:sched/core] sched/numa: Update the scan period without holding the numa_group lock tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 15/19] sched/numa: Use group_weights to identify if migration degrades locality Srikar Dronamraju
2018-07-25 14:29 ` [tip:sched/core] " tip-bot for Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 16/19] sched/numa: Detect if node actively handling migration Srikar Dronamraju
2018-06-20 17:02 ` [PATCH v2 17/19] sched/numa: Pass destination cpu as a parameter to migrate_task_rq Srikar Dronamraju
2018-06-20 17:02 ` Srikar Dronamraju [this message]
2018-06-21 10:05 ` [PATCH v2 18/19] sched/numa: Reset scan rate whenever task moves across nodes Mel Gorman
2018-07-04 11:19 ` Srikar Dronamraju
2018-06-20 17:03 ` [PATCH v2 19/19] sched/numa: Move task_placement closer to numa_migrate_preferred Srikar Dronamraju
2018-06-21 10:06 ` Mel Gorman
2018-07-25 14:30 ` [tip:sched/core] sched/numa: Move task_numa_placement() closer to numa_migrate_preferred() tip-bot for Srikar Dronamraju
2018-06-20 17:03 ` [PATCH v2 00/19] Fixes for sched/numa_balancing Srikar Dronamraju
2018-07-23 13:57 ` Peter Zijlstra
2018-07-23 15:09 ` Srikar Dronamraju
2018-07-23 15:21 ` Peter Zijlstra
2018-07-23 16:29 ` Srikar Dronamraju
2018-07-23 16:47 ` Peter Zijlstra
2018-07-23 15:33 ` Rik van Riel
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