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Date: Tue, 4 Oct 2016 15:14:27 -0400
From: Tejun Heo <tj@kernel.org>
To: Paolo Valente <paolo.valente@unimore.it>
Cc: Shaohua Li <shli@fb.com>, Vivek Goyal <vgoyal@redhat.com>,
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        Linus Walleij <linus.walleij@linaro.org>,
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Subject: Re: [PATCH V3 00/11] block-throttle: add .high limit
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Hello, Paolo.

On Tue, Oct 04, 2016 at 09:02:47PM +0200, Paolo Valente wrote:
> That's exactly what BFQ has succeeded in doing in all the tests
> devised so far.  Can you give me a concrete example for which I can
> try with BFQ and with any other mechanism you deem better.  If
> you are right, numbers will just make your point.

Hmm... I think we already discussed this but here's a really simple
case.  There are three unknown workloads A, B and C and we want to
give A certain best-effort guarantees (let's say around 80% of the
underlying device) whether A is sharing the device with B or C.

I get that bfq can be a good compromise on most desktop workloads and
behave reasonably well for some server workloads with the slice
expiration mechanism but it really isn't an IO resource partitioning
mechanism.

Thanks.

-- 
tejun