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From: Marcelo Tosatti <mtosatti@redhat.com>
To: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc: Luiz Capitulino <lcapitulino@redhat.com>,
	Rik van Riel <riel@redhat.com>,
	Linux RT Users <linux-rt-users@vger.kernel.org>
Subject: [patch 0/3] per-CPU vmstat thresholds and vmstat worker disablement (v2)
Date: Wed, 03 May 2017 15:40:07 -0300	[thread overview]
Message-ID: <20170503184007.174707977@redhat.com> (raw)

The per-CPU vmstat worker is a problem on -RT workloads (because
ideally the CPU is entirely reserved for the -RT app, without
interference). The worker transfers accumulated per-CPU
vmstat counters to global counters.

To resolve the problem, create two tunables:

* Userspace configurable per-CPU vmstat threshold: by default the
VM code calculates the size of the per-CPU vmstat arrays. This
tunable allows userspace to configure the values.

* Userspace configurable per-CPU vmstat worker: allow disabling
the per-CPU vmstat worker.

v2:
- Improve documentation (Rik/Luiz).
- Split patch in two (Luiz).
- Fix comparison to include equal, in the helpers for
stats accounting.



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             reply	other threads:[~2017-05-03 18:40 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-05-03 18:40 Marcelo Tosatti [this message]
2017-05-03 18:40 ` [patch 1/3] MM: remove unused quiet_vmstat function Marcelo Tosatti
2017-05-10 13:36   ` Rik van Riel
2017-05-03 18:40 ` [patch 2/3] MM: allow per-cpu vmstat_threshold configuration Marcelo Tosatti
2017-05-03 18:40 ` [patch 3/3] MM: allow per-cpu vmstat_worker configuration Marcelo Tosatti
2017-05-10 15:34   ` Rik van Riel
2017-05-11 15:33     ` Marcelo Tosatti
2017-05-16  1:31   ` [lkp-robot] [MM] 3e38a07a66: ltp.proc01.fail kernel test robot

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