Message-ID: <41F786EF.9FE19AEC@tv-sign.ru>
Date: Wed, 26 Jan 2005 15:02:55 +0300
From: Oleg Nesterov <oleg@tv-sign.ru>
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To: Ram <linuxram@us.ibm.com>
Cc: linux-kernel@vger.kernel.org, Steven Pratt <slpratt@austin.ibm.com>,
       Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH 2/4] page_cache_readahead: remove duplicated code
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Ram wrote:
>
> No. There is a reason why we had some duplication. With your patch,
> we will end up reading-on-demand instead of reading ahead.
>
> When we notice a sequential reads have resumed, we first read in the
> data that is requested.
> However if the read request is for more pages than what are being held
> in the current window, we make the ahead window as the current window
> and read in more pages in the ahead window. Doing that gives the
> opportunity of always having pages in the ahead window when the next
> sequential read request comes in.

Yes, sorry. I have not noticed that this 'goto out' is conditional in
the 'no ahead window' case.

Thank you for explanation.

However, I still think it makes sense to factor out the common code in
these two cases, just for readability.

I'll redo these patches.

Oleg.
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