linux-kernel - Re: [RFCv2][PATCH] add some drop_caches documentation and info messsge

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] [day] [month] [year] [list]

Message-Id: <20100921100011.86f270de.kamezawa.hiroyu@jp.fujitsu.com>
Date:	Tue, 21 Sep 2010 10:00:11 +0900
From:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
To:	Dave Hansen <dave@...ux.vnet.ibm.com>
Cc:	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	lnxninja@...ux.vnet.ibm.com, ebiederm@...ssion.com,
	kosaki.motohiro@...fujitsu.com
Subject: Re: [RFCv2][PATCH] add some drop_caches documentation and info
 messsge

On Thu, 16 Sep 2010 09:50:47 -0700
Dave Hansen <dave@...ux.vnet.ibm.com> wrote:

> 
> This version tones down the BUG_ON().  I also noticed that the
> documentation fails to mention that more than just the inode
> and dentry slabs are shrunk.
> 
> --
> 
> There is plenty of anecdotal evidence and a load of blog posts
> suggesting that using "drop_caches" periodically keeps your system
> running in "tip top shape".  Perhaps adding some kernel
> documentation will increase the amount of accurate data on its use.
> 
> If we are not shrinking caches effectively, then we have real bugs.
> Using drop_caches will simply mask the bugs and make them harder
> to find, but certainly does not fix them, nor is it an appropriate
> "workaround" to limit the size of the caches.
> 
> It's a great debugging tool, and is really handy for doing things
> like repeatable benchmark runs.  So, add a bit more documentation
> about it, and add a little KERN_NOTICE.  It should help developers
> who are chasing down reclaim-related bugs.
> 
> Signed-off-by: Dave Hansen <dave@...ux.vnet.ibm.com>

Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>

thanks.

--
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/