linux-kernel - Re: [RFT][PATCH] mm: drop behind

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, 12 Jul 2007 09:24:46 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Tim Pepper <lnxninja@...ibm.com>
Cc:	linux-kernel <linux-kernel@...r.kernel.org>,
	linux-mm <linux-mm@...ck.org>,
	Fengguang Wu <wfg@...l.ustc.edu.cn>, riel <riel@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Rusty Russell <rusty@...tcorp.com.au>
Subject: Re: [RFT][PATCH] mm: drop behind

Hi Tim,

On Wed, 2007-07-11 at 15:37 -0700, Tim Pepper wrote:
> On 7/9/07, Peter Zijlstra <peterz@...radead.org> wrote:
> > Use the read-ahead code to provide hints to page reclaim.
> >
> > This patch has the potential to solve the streaming-IO trashes my
> > desktop problem.
> >
> > It tries to aggressively reclaim pages that were loaded in a strong
> > sequential pattern and have been consumed. Thereby limiting the damage
> > to the current resident set.
> 
> Interesting...
> 
> Would it make sense to tie this into (finally) making
> POSIX_FADV_NOREUSE something more than a noop?

We talked about that, but the thing is, if we make the functionality
conditional, nobody will ever use it :-/

So, yes, in a perfect world that would indeed make sense. However since
nobody ever uses these [fm]advise calls,..

So the big question is, does this functionally hurt any workload? If it
turns out it does (which I still doubt) then we might hide it behind
knobs, otherwise I'd like to keep it always on.

Peter



-
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/