Date: Tue, 19 Dec 2017 10:03:37 -0600 (CST)
From: Christopher Lameter <cl@linux.com>
To: Frederic Weisbecker <frederic@kernel.org>
cc: LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Chris Metcalf <cmetcalf@mellanox.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Luiz Capitulino <lcapitulino@redhat.com>,
        "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>,
        Ingo Molnar <mingo@kernel.org>, Wanpeng Li <kernellwp@gmail.com>,
        Mike Galbraith <efault@gmx.de>, Rik van Riel <riel@redhat.com>
Subject: Re: [PATCH 4/5] sched/isolation: Residual 1Hz scheduler tick
 offload
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On Tue, 19 Dec 2017, Frederic Weisbecker wrote:

> Adding the boot parameter "isolcpus=nohz_offload" will now outsource
> these scheduler ticks to the global workqueue so that a housekeeping CPU
> handles that tick remotely.

The vmstat processing required per cpu area access. How does that work if
the code is running on a remote processor?