From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH v2] blk-throttle: simplify logic by token bucket algorithm
Date: Mon, 14 Oct 2013 09:36:20 -0400
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To: Hong Zhiguo <honkiko-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org, vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Hong Zhiguo <zhiguohong-1Nz4purKYjRBDgjK7y7TUQ@public.gmane.org>

Hello,

On Mon, Oct 14, 2013 at 05:09:17PM +0800, Hong Zhiguo wrote:
> From: Hong Zhiguo <zhiguohong-1Nz4purKYjRBDgjK7y7TUQ@public.gmane.org>
> 
> Token bucket algorithm(http://en.wikipedia.org/wiki/Token_bucket)
> is very simple and widely used for rate limiting and shaping.
> It's well suitable for blk-throttle. And it natually works for
> hierarchical cgroups. So I took it to replace the original time
> _slicing_|_trimming_|_extending_ logic.
> 
> The advantage is simplicity, reliability and less fluctuation.
> 
> About 300 lines of code for time-slicing is replaced with 60 lines of
> code for token bucket in blk-throttle.c.
> 
> I've tested this patch by fio with rw=randread, rw=randrw. It
> behaves almost the same with original time-slicing implementation,
> and with more accuracy.

Yes, this definitely is the direction we wanna take it.  I'll wait for
Vivek to chime in but have you also tested hierarchical setup?

Thanks.

-- 
tejun