From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH v4 0/5] getcpu_cache system call for 4.6
Date: Tue, 23 Feb 2016 17:36:26 -0800
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References: <1456270120-7560-1-git-send-email-mathieu.desnoyers@efficios.com>
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On 02/23/2016 03:28 PM, Mathieu Desnoyers wrote:
> Hi,
> 
> Here is a patchset implementing a cache for the CPU number of the
> currently running thread in user-space.
> 
> Benchmarks comparing this approach to a getcpu based on system call on
> ARM show a 44x speedup. They show a 14x speedup on x86-64 compared to
> executing lsl from a vDSO through glibc.
> 
> I'm added a man page in the changelog of patch 1/3, which shows an
> example usage of this new system call.
> 
> This series is based on v4.5-rc5, submitted for Linux 4.6.
> 
> Feedback is welcome,
> 

What is the resulting context switch overhead?

	-hpa