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Date: Thu, 10 Oct 2013 20:35:17 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>, Andrew Morton <akpm@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>, Mel Gorman <mgorman@suse.de>,
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        Andrea Arcangeli <aarcange@redhat.com>,
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        Thomas Gleixner <tglx@linutronix.de>,
        Steven Rostedt <rostedt@goodmis.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/6] Optimize the cpu hotplug locking -v2
Message-ID: <20131010183517.GQ13848@laptop.programming.kicks-ass.net>
References: <20131008102505.404025673@infradead.org>
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On Thu, Oct 10, 2013 at 10:13:53AM -0700, Paul E. McKenney wrote:
> That does add quite a bit of latency to the hotplug operations, which
> IIRC slows down things like boot, suspend, and resume.

Guess what suspend does before it unplugs all these cpus?