From: Mel Gorman <mgorman@techsingularity.net>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>,
Ingo Molnar <mingo@kernel.org>,
Juri Lelli <juri.lelli@redhat.com>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>,
Valentin Schneider <valentin.schneider@arm.com>,
Phil Auld <pauld@redhat.com>, Hillf Danton <hdanton@sina.com>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 00/13] Reconcile NUMA balancing decisions with the load balancer v3
Date: Mon, 17 Feb 2020 15:31:06 +0000 [thread overview]
Message-ID: <20200217153106.GL3466@techsingularity.net> (raw)
In-Reply-To: <20200217145216.GR14897@hirez.programming.kicks-ass.net>
On Mon, Feb 17, 2020 at 03:52:16PM +0100, Peter Zijlstra wrote:
> On Mon, Feb 17, 2020 at 02:49:11PM +0100, Vincent Guittot wrote:
> > > Patches 4-5 are Vincent's and use very similar code patterns and logic
> > > between NUMA and load balancer. Patch 6 is a fix to Vincent's work that
> > > is necessary to avoid serious imbalances being introduced by the NUMA
> >
> > Yes the test added in load_too_imbalanced() by patch 5 doesn't seem to
> > be a good choice.
> > I haven't remove it as it was done by your patch 6 but it might worth
> > removing it directly if a new version is needed
>
> Aside of that, Vincent's patches look good to me.
Fully agreed, I think it's now much easier to understand the two balancers
when put side by side in addition to getting some performance gains.
Even if a regression is found, I think it'll be due to a workload seeing
an advantage when NUMA balancer constantly overrides the load balancer.
If that happens, the imbalance can be governed by adjust_numa_balance so
that the two balancers avoid fighting each other again.
--
Mel Gorman
SUSE Labs
next prev parent reply other threads:[~2020-02-17 15:31 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-17 10:43 Mel Gorman
2020-02-17 10:43 ` [PATCH 01/13] sched/fair: Allow a per-CPU kthread waking a task to stack on the same CPU, to fix XFS performance regression Mel Gorman
2020-02-17 10:43 ` [PATCH 02/13] sched/numa: Trace when no candidate CPU was found on the preferred node Mel Gorman
2020-02-17 10:43 ` [PATCH 03/13] sched/numa: Distinguish between the different task_numa_migrate failure cases Mel Gorman
2020-02-17 10:43 ` [PATCH 04/13] sched/fair: Reorder enqueue/dequeue_task_fair path Mel Gorman
2020-02-17 10:43 ` [PATCH 05/13] sched/numa: Replace runnable_load_avg by load_avg Mel Gorman
2020-02-17 10:43 ` [PATCH 06/13] sched/numa: Use similar logic to the load balancer for moving between domains with spare capacity Mel Gorman
2020-02-17 10:43 ` [PATCH 07/13] sched/pelt: Remove unused runnable load average Mel Gorman
2020-02-17 10:43 ` [PATCH 08/13] sched/pelt: Add a new runnable average signal Mel Gorman
2020-02-17 10:43 ` [PATCH 09/13] sched/fair: Take into account runnable_avg to classify group Mel Gorman
2020-02-17 10:43 ` [PATCH 10/13] sched/numa: Prefer using an idle cpu as a migration target instead of comparing tasks Mel Gorman
2020-02-17 10:44 ` [PATCH 11/13] sched/numa: Find an alternative idle CPU if the CPU is part of an active NUMA balance Mel Gorman
2020-02-17 10:44 ` [PATCH 12/13] sched/numa: Bias swapping tasks based on their preferred node Mel Gorman
2020-02-17 10:44 ` [PATCH 13/13] sched/numa: Stop an exhastive search if a reasonable swap candidate or idle CPU is found Mel Gorman
2020-02-17 13:49 ` [PATCH 00/13] Reconcile NUMA balancing decisions with the load balancer v3 Vincent Guittot
2020-02-17 14:52 ` Peter Zijlstra
2020-02-17 15:31 ` Mel Gorman [this message]
2020-02-17 15:14 ` Mel Gorman
2020-02-17 16:15 ` Vincent Guittot
[not found] ` <20200217132019.6684-1-hdanton@sina.com>
2020-02-17 15:06 ` [PATCH 06/13] sched/numa: Use similar logic to the load balancer for moving between domains with spare capacity Mel Gorman
[not found] ` <20200218033244.6860-1-hdanton@sina.com>
2020-02-18 8:47 ` Mel Gorman
[not found] ` <20200218095915.844-1-hdanton@sina.com>
2020-02-18 10:53 ` Mel Gorman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200217153106.GL3466@techsingularity.net \
--to=mgorman@techsingularity.net \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=hdanton@sina.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=pauld@redhat.com \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=valentin.schneider@arm.com \
--cc=vincent.guittot@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome