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Subject: Re: [PATCH] iosched: Add i10 I/O Scheduler
To:     Jens Axboe <axboe@kernel.dk>, Rachit Agarwal <rach4x0r@gmail.com>,
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        Qizhe Cai <qc228@cornell.edu>,
        Midhul Vuppalapati <mvv25@cornell.edu>,
        Rachit Agarwal <ragarwal@cs.cornell.edu>,
        Sagi Grimberg <sagi@lightbitslabs.com>,
        Rachit Agarwal <ragarwal@cornell.edu>
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From:   Sagi Grimberg <sagi@grimberg.me>
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Date:   Fri, 13 Nov 2020 13:36:16 -0800
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>> But if you think this has a better home, I'm assuming that the guys
>> will be open to that.
> 
> Also see the reply from Ming. It's a balancing act - don't want to add
> extra overhead to the core, but also don't want to carry an extra
> scheduler if the main change is really just variable dispatch batching.
> And since we already have a notion of that, seems worthwhile to explore
> that venue.

I agree,

The main difference is that this balancing is not driven from device
resource pressure, but rather from an assumption of device specific
optimization (and also with a specific optimization target), hence a
scheduler a user would need to opt-in seemed like a good compromise.

But maybe Ming has some good ideas on a different way to add it..