From: Mike Galbraith <efault@gmx.de>
To: Rohit Jain <rohit.k.jain@oracle.com>, linux-kernel@vger.kernel.org
Cc: peterz@infradead.org, mingo@redhat.com,
steven.sistare@oracle.com, joelaf@google.com, jbacik@fb.com,
riel@redhat.com, juri.lelli@redhat.com, dhaval.giani@oracle.com
Subject: Re: [RFC 2/2] Introduce sysctl(s) for the migration costs
Date: Fri, 09 Feb 2018 04:54:07 +0100 [thread overview]
Message-ID: <1518148447.24350.34.camel@gmx.de> (raw)
In-Reply-To: <1518128395-14606-3-git-send-email-rohit.k.jain@oracle.com>
On Thu, 2018-02-08 at 14:19 -0800, Rohit Jain wrote:
> This patch introduces the sysctl for sched_domain based migration costs.
> These in turn can be used for performance tuning of workloads.
With this patch, we trade 1 completely bogus constant (cost is really
highly variable) for 3, twiddling of which has zero effect unless you
trigger a domain rebuild afterward, which is neither mentioned in the
changelog, nor documented.
bogo-numbers++ is kinda hard to love.
-Mike
next prev parent reply other threads:[~2018-02-09 3:54 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-08 22:19 [RFC 0/2] sched: Make idle_balance smarter about topology Rohit Jain
2018-02-08 22:19 ` [RFC 1/2] sched: reduce migration cost between faster caches for idle_balance Rohit Jain
2018-02-09 3:42 ` Mike Galbraith
2018-02-09 16:08 ` Steven Sistare
2018-02-10 6:37 ` Mike Galbraith
2018-02-15 16:35 ` Steven Sistare
2018-02-15 18:07 ` Mike Galbraith
2018-02-15 18:21 ` Steven Sistare
2018-02-15 18:39 ` Mike Galbraith
2018-02-15 18:07 ` Rohit Jain
2018-02-16 4:53 ` Mike Galbraith
2018-02-08 22:19 ` [RFC 2/2] Introduce sysctl(s) for the migration costs Rohit Jain
2018-02-09 3:54 ` Mike Galbraith [this message]
2018-02-09 16:10 ` Steven Sistare
2018-02-09 17:08 ` Mike Galbraith
2018-02-09 17:33 ` Steven Sistare
2018-02-09 17:50 ` Mike Galbraith
2018-02-12 15:28 ` Peter Zijlstra
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