linux-kernel - Re: [PATCH] vmscan: evict use-once pages first (v3)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 30 Apr 2009 10:10:29 +0200
From:	Johannes Weiner <hannes@...xchg.org>
To:	Rik van Riel <riel@...hat.com>
Cc:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Elladan <elladan@...imo.com>, linux-kernel@...r.kernel.org,
	tytso@....edu, linux-mm@...ck.org
Subject: Re: [PATCH] vmscan: evict use-once pages first (v3)

On Wed, Apr 29, 2009 at 01:14:36PM -0400, Rik van Riel wrote:
> When the file LRU lists are dominated by streaming IO pages,
> evict those pages first, before considering evicting other
> pages.
> 
> This should be safe from deadlocks or performance problems
> because only three things can happen to an inactive file page:
> 1) referenced twice and promoted to the active list
> 2) evicted by the pageout code
> 3) under IO, after which it will get evicted or promoted
> 
> The pages freed in this way can either be reused for streaming
> IO, or allocated for something else. If the pages are used for
> streaming IO, this pageout pattern continues. Otherwise, we will
> fall back to the normal pageout pattern.
> 
> Signed-off-by: Rik van Riel <riel@...hat.com>

Although Elladan didn't test this exact patch, he reported on v2 that
the general idea of scanning active files only when they exceed the
inactive set works.

Acked-by: Johannes Weiner <hannes@...xchg.org>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/