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Date: Sun, 2 Nov 2014 18:20:39 -0700
From: Jens Axboe <axboe@fb.com>
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To: Richard Weinberger <richard@nod.at>, Ezequiel Garcia
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Subject: Re: [PATCH] UBI: Block: Add blk-mq support
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On 2014-11-02 15:49, Richard Weinberger wrote:
> AFAICT blk-mq allocates one struct ubiblock_pdu per device.
> As all IO is done via scattergather the memory footprint should be good.
> But I'm sure Christoph can tell you the glory details.

That is true, the request list and pdu is allocated upfront. If that is 
a problem, the pdu need not be allocated upfront but could be done at IO 
time instead. With that comes a bit more complicated retry handling, for 
memory shortage situations.

-- 
Jens Axboe