Date: Thu, 27 Oct 2016 17:55:33 +0200
From: Heinz Diehl <htd+ml@fritha.org>
To: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 00/14] introduce the BFQ-v0 I/O scheduler as an extra
 scheduler
Message-ID: <20161027155533.GA4761@fritha.org>
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On 27.10.2016, Grozdan wrote: 

> So in the end, I'm here to support the inclusion of BFQ. Paolo has put
> too much energy, time, and sleepless nights into this so people like
> me can have a working, responsive system during heavy disk operations.
> From a normal user's perspective, I do not want BFQ to be dismissed
> and all the effort/time/etc thrown out the window. From my
> perspective, Paolo deserves more support from the guys in charge of
> the block layer in Linux.

I really  want to second that!

Just take a bog-standard desktop PC with an SSD and a reasonably fast
CPU (an 8-core Xeon in my case) and do the following:

1. dd if=/dev/zero of=deleteme bs=1M count=50000
2. Start oowriter (Libreoffice Writer)

Using both cfq, deadline or noop, oowriter does not load until dd'ing
the 50 gigs is finished. Using bfq, oowriter loads nearly immediately.

Not to mention that both cfq, deadline and noop are a nightmare on
Android in terms of latency.

I'm (obviously) neither a kernel nor a bfq developer, but I really
want you to reconsider, with the overall greatness of bfq in mind, if
it really is totally impossible to include it at least as a scheduler
option, alongside the other three already existing ones.

Thanks,
 Heinz