Date: Mon, 28 Nov 2016 17:08:18 -0500
From: Tejun Heo <tj@kernel.org>
To: Shaohua Li <shli@fb.com>
Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        Kernel-team@fb.com, axboe@fb.com, vgoyal@redhat.com
Subject: Re: [PATCH V4 11/15] blk-throttle: add interface to configure think
 time threshold
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Hello, Shaohua.

On Wed, Nov 23, 2016 at 05:06:30PM -0800, Shaohua Li wrote:
> > Shouldn't this be a per-cgroup setting along with latency target?
> > These two are the parameters which define how the cgroup should be
> > treated time-wise.
> 
> It should be easy to make it per-cgroup. Just not sure if it should be
> per-cgroup. The logic is if the disk is faster, wait time should be shorter to
> not harm performance. So it sounds like a per-disk characteristic.

Yes, this is something dependent on the device, but also on the
workload.  For both this parameter and the latency target, it seems
that they should be specified along with the actual device limits so
that they follow the same convention and can be specified per cgroup *
block device.  What do you think?

Thanks.

-- 
tejun