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Date: Thu, 19 Aug 2010 05:26:13 +0800
From: Wu Fengguang <fengguang.wu@intel.com>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@linux.intel.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Li Shaohua <shaohua.li@intel.com>,
        Rik van Riel <riel@redhat.com>
Subject: Re: [TESTCASE] Clean pages clogging the VM
Message-ID: <20100818212613.GA7366@localhost>
References: <20100809133000.GB6981@wil.cx>
 <20100817195001.GA18817@linux.intel.com>
 <20100818141308.GD1779@cmpxchg.org>
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> Mapped file pages get two rounds on the LRU list, so once the VM
> starts scanning, it has to go through all of them twice and can only
> reclaim them on the second encounter.

This can be fixed gracefully based on Rik's refault-distance patch :)
With the distance info we can safely drop the use-once mapped file pages.

Thanks,
Fengguang

From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Thu, 19 Aug 2010 05:26:13 +0800
From: Wu Fengguang <fengguang.wu@intel.com>
Subject: Re: [TESTCASE] Clean pages clogging the VM
Message-ID: <20100818212613.GA7366@localhost>
References: <20100809133000.GB6981@wil.cx>
 <20100817195001.GA18817@linux.intel.com>
 <20100818141308.GD1779@cmpxchg.org>
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To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@linux.intel.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Li Shaohua <shaohua.li@intel.com>, Rik van Riel <riel@redhat.com>
List-ID: <linux-mm.kvack.org>

> Mapped file pages get two rounds on the LRU list, so once the VM
> starts scanning, it has to go through all of them twice and can only
> reclaim them on the second encounter.

This can be fixed gracefully based on Rik's refault-distance patch :)
With the distance info we can safely drop the use-once mapped file pages.

Thanks,
Fengguang

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