linux-kernel - Re: [PATCH -mm 2/2] mm: do not reset mm->free_area

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]

Message-ID: <m2vcmxp609.fsf@firstfloor.org>
Date:	Thu, 23 Feb 2012 13:57:42 -0800
From:	Andi Kleen <andi@...stfloor.org>
To:	Rik van Riel <riel@...hat.com>
Cc:	linux-mm@...ck.org, linux-kernel@...r.kernel.org,
	akpm@...ux-foundation.org, Mel Gorman <mel@....ul.ie>,
	Johannes Weiner <hannes@...xchg.org>,
	KOSAKI Motohiro <kosaki.motohiro@...il.com>,
	Andrea Arcangeli <aarcange@...hat.com>, hughd@...gle.com
Subject: Re: [PATCH -mm 2/2] mm: do not reset mm->free_area_cache on every single munmap

Rik van Riel <riel@...hat.com> writes:

> Some programs have a large number of VMAs, and make frequent calls
> to mmap and munmap. Having munmap constantly cause the search
> pointer for get_unmapped_area to get reset can cause a significant
> slowdown for such programs. 

This would be a much nicer patch if you split it into one that merges
all the copy'n'paste code and another one that actually implements
the new algorithm.

-Andi

-- 
ak@...ux.intel.com -- Speaking for myself only
--
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/