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Message-ID: <28c262360806081914v357f4093ra1e1e9e36f487eb7@mail.gmail.com>
Date: Mon, 9 Jun 2008 11:14:55 +0900
From: "MinChan Kim" <minchan.kim@gmail.com>
To: "Rik van Riel" <riel@redhat.com>
Subject: Re: [PATCH -mm 04/25] free swap space on swap-in/activation
Cc: "Andrew Morton" <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org,
       lee.schermerhorn@hp.com, kosaki.motohiro@jp.fujitsu.com,
       "Hugh Dickins" <hugh@veritas.com>
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> - Can completely optimise the thing away if !CONFIG_SWAP.
>

I think we can optimize more and more in case of if !CONFIG_SWAP.
If system are !CONFIG_SWAP, we can never  swap out anonymous pages.

Don't we manage anonymous pages with list ?

Such system don't need to insert anonymous pages into lru list when fault occur.
It is just needless overhead.

Also, If we can't reclaim anonymous pages, don't we need anon rmap facility ?
I don't know well which subsystems used rmap.

If pageout only use anonymous rmap for pageout,
we can remove anonymous rmapping code in case of !CONFIG_SWAP

How about your opinion ?

-- 
Kinds regards,
MinChan Kim