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Date: Sat, 2 Feb 2002 13:57:49 +0100
From: Jens Axboe <axboe@suse.de>
To: Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua>
Cc: Arnaldo Carvalho de Melo <acme@conectiva.com.br>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Re: crc32 and lib.a (was Re: [PATCH] nbd in 2.5.3 does
Message-ID: <20020202135749.B4934@suse.de>
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> include/linux/blk.h
> 
>         Changed NR_REQUEST from 256 to 16.  This reduces the number of
>         requests that can be queued.  The size of the queue is reduced
>         from 16K to 1K.

You can do even more than this -- I dunno what I/O interface these
embedded system generally uses (the mtd stuff?). Provided you provide a
direct make_request_fn entry into these instead of using the queue, you
can basically cut all of ll_rw_blk.c and elevator.c. ll_rw_block,
submit_bh, and generic_make_request would be all that is left.

That should reclaim quite a lot of space. If there's any interest in
this (has it already been done?), I can help out getting it done.

-- 
Jens Axboe

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