Message-ID: <563CE5A6.8080409@hpe.com>
Date: Fri, 06 Nov 2015 12:38:46 -0500
From: Waiman Long <waiman.long@hpe.com>
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To: Ling Ma <ling.ma.program@gmail.com>
CC: Peter Zijlstra <peterz@infradead.org>, mingo@redhat.com,
        linux-kernel@vger.kernel.org, Ling <ling.ml@alibaba-inc.com>
Subject: Re: Improve spinlock performance by moving work to one core
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On 11/05/2015 11:28 PM, Ling Ma wrote:
> Longman
>
> Thanks for your suggestion.
> We will look for real scenario to test, and could you please introduce
> some benchmarks on spinlock ?
>
> Regards
> Ling
>
>

The kernel has been well optimized for most common workloads that 
spinlock contention is usually not a performance bottleneck. There are 
still corner cases where there is heavy spinlock contention.

I used a spinlock loop microbenchmark like what you are doing as well as 
AIM7 for application level testing.

Cheers,
Longman


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