linux-kernel - Re: [PATCH 1/3] mm/page_alloc: don't break highest order freepage if steal

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:	Mon, 27 Apr 2015 09:08:50 +0100
From:	Mel Gorman <mgorman@...e.de>
To:	Joonsoo Kim <iamjoonsoo.kim@....com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	Vlastimil Babka <vbabka@...e.cz>,
	Johannes Weiner <hannes@...xchg.org>,
	Rik van Riel <riel@...hat.com>
Subject: Re: [PATCH 1/3] mm/page_alloc: don't break highest order freepage if
 steal

On Mon, Apr 27, 2015 at 04:23:39PM +0900, Joonsoo Kim wrote:
> When we steal whole pageblock, we don't need to break highest order
> freepage. Perhaps, there is small order freepage so we can use it.
> 

The reason why the largest block is taken is to reduce the probability
there will be another fallback event in the near future. Early on, there
were a lot of tests conducted to measure the number of external fragmenting
events and take steps to reduce them. Stealing the largest highest order
freepage was one of those steps.

-- 
Mel Gorman
SUSE Labs
--
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/