linux-kernel - Re: [PATCH 5/5] writeback: Reporting dirty thresholds in /proc/vmstat

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: <20100913142412.dc0f6950.akpm@linux-foundation.org>
Date:	Mon, 13 Sep 2010 14:24:12 -0700
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Michael Rubin <mrubin@...gle.com>
Cc:	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
	linux-mm@...ck.org, fengguang.wu@...el.com, jack@...e.cz,
	riel@...hat.com, david@...morbit.com,
	kosaki.motohiro@...fujitsu.com, npiggin@...nel.dk, hch@....de,
	axboe@...nel.dk
Subject: Re: [PATCH 5/5] writeback: Reporting dirty thresholds in
 /proc/vmstat

On Sun, 12 Sep 2010 22:58:13 -0700
Michael Rubin <mrubin@...gle.com> wrote:

> The kernel already exposes the user desired thresholds in /proc/sys/vm
> with dirty_background_ratio and background_ratio. But the kernel may
> alter the number requested without giving the user any indication that
> is the case.
> 
> Knowing the actual ratios the kernel is honoring can help app developers
> understand how their buffered IO will be sent to the disk.
> 
>         $ grep threshold /proc/vmstat
>         nr_dirty_threshold 409111
>         nr_dirty_background_threshold 818223
> 

Yes, I think /proc/vmstat is a decent place to put these.  The needed
infrastructural support is minimal and although these numbers are
closely tied to the implementation-of-the-day, people should expect
individual fields in /proc/vmstat to appear and disappear at random as
kernel versions change.

--
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/