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Date: Mon, 3 Feb 2014 12:40:54 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Waiman Long <waiman.long@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Arnd Bergmann <arnd@arndb.de>,
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        George Spelvin <linux@horizon.com>,
        Tim Chen <tim.c.chen@linux.intel.com>,
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        Thavatchai Makphaibulchoke <thavatchai.makpahibulchoke@hp.com>
Subject: Re: [PATCH v3 1/2] qspinlock: Introducing a 4-byte queue spinlock
 implementation
Message-ID: <20140203114054.GH8874@twins.programming.kicks-ass.net>
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On Fri, Jan 31, 2014 at 02:24:33PM -0500, Waiman Long wrote:
> 
> Light contention is the only case where the qspinlock may not perform as
> good as the ticket spinlock. I know this is the most common case. However, I
> would argue that the slowdown, if any, will not be really noticeable. This
> is what I will try to find out.

Please also explain why things are slower/faster. Thomas tried to get
you to do so a few months back, but you kept deflecting.