linux-kernel - Re: block cache replacement strategy?

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:	Tue, 14 Sep 2010 05:09:31 +1000
From:	dave b <db.pub.mail@...il.com>
To:	Johannes Stezenbach <js@...21.net>
Cc:	Florian Mickler <florian@...kler.org>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	linux-fsdevel@...r.kernel.org
Subject: Re: block cache replacement strategy?

On 14 September 2010 01:21, Johannes Stezenbach <js@...21.net> wrote:
> On Fri, Sep 10, 2010 at 06:02:48PM +0200, Johannes Stezenbach wrote:
>>
>> Linear read heuristic might be a good guess, but it would
>> be nice to hear a comment from a vm/fs expert which
>> confirms this works as intended.
>
> Apparently I'm unworthy to get a response from someone knowledgable :-(
>
> Anyway I found lmdd (from lmbench) can do random reads,
> and indeed causes the data to enter the block (page?) cache,
> replacing the previous data.


I am no expert, but what did you think would happen if you did dd
twice from /dev/zero?
but... Honestly what do you think will be cached?
If you want 'COW', use btrfs.

--
Conscience doth make cowards of us all.		-- Shakespeare
--
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/