From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 91F8A8D0039 for ; Wed, 2 Mar 2011 22:11:04 -0500 (EST) Received: by iyf13 with SMTP id 13so712320iyf.14 for ; Wed, 02 Mar 2011 19:11:02 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20110302082412.87f153ba.rdunlap@xenotime.net> References: <1299055090-23976-1-git-send-email-namei.unix@gmail.com> <20110302082412.87f153ba.rdunlap@xenotime.net> Date: Thu, 3 Mar 2011 11:11:02 +0800 Message-ID: Subject: Re: [RFC PATCH 1/5] x86/Kconfig: Add Page Cache Accounting entry From: Liu Yuan Content-Type: multipart/alternative; boundary=20cf305644751d1c2f049d8b61fe Sender: owner-linux-mm@kvack.org List-ID: To: Randy Dunlap Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, jaxboe@fusionio.com, akpm@linux-foundation.org, fengguang.wu@intel.com --20cf305644751d1c2f049d8b61fe Content-Type: text/plain; charset=ISO-8859-1 On Thu, Mar 3, 2011 at 12:24 AM, Randy Dunlap wrote: > On Wed, 2 Mar 2011 16:38:06 +0800 Liu Yuan wrote: > > > From: Liu Yuan > > > > Signed-off-by: Liu Yuan > > --- > > arch/x86/Kconfig.debug | 9 +++++++++ > > 1 files changed, 9 insertions(+), 0 deletions(-) > > > > diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug > > index 615e188..f29e32d 100644 > > --- a/arch/x86/Kconfig.debug > > +++ b/arch/x86/Kconfig.debug > > @@ -304,4 +304,13 @@ config DEBUG_STRICT_USER_COPY_CHECKS > > > > If unsure, or if you run an older (pre 4.4) gcc, say N. > > > > +config PAGE_CACHE_ACCT > > + bool "Page cache accounting" > > + ---help--- > > + Enabling this options to account for page cache hit/missed number > of > > + times. This would allow user space applications get better > knowledge > > + of underlying page cache system by reading virtual file. The > statitics > > + per partition are collected. > > + > > + If unsure, say N. > > endmenu > > -- > > rewrite: > > Enable this option to provide for page cache hit/miss counters. > This allows userspace applications to obtain better knowledge of > the > underlying page cache subsystem by reading a virtual file. > Statistics are collect per partition. > > questions: > what virtual file? > what kind of partition? > > Hi Randy, Thanks for your correction. 'virtual file' in this patch context means files in sysfs mounted at /sys. 'partition' indicates that every disk partition (like /dev/sda/{sda1,sda2...} has its own accountings for page cache information. I am not confident about phrasing. so please correct it if you think it is way better. Thanks, Liu Yuan --20cf305644751d1c2f049d8b61fe Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable

On Thu, Mar 3, 2011 at 12:24 AM, Randy D= unlap <rdunlap= @xenotime.net> wrote:
On Wed, =A02 Mar 2011 16:38:06 +0800 Liu = Yuan wrote:

> From: Liu Yuan <tail= ai.ly@taobao.com>= ;
>
> Signed-off-by: Liu Yuan <tailai.ly@taobao.c= om>
> ---
> =A0arch/x86/Kconfig.debug | =A0 =A09 +++++++++
> =A01 files changed, 9 insertions(+), 0 deletions(-)
>
> diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
> index 615e188..f29e32d 100644
> --- a/arch/x86/Kconfig.debug
> +++ b/arch/x86/Kconfig.debug
> @@ -304,4 +304,13 @@ config DEBUG_STRICT_USER_COPY_CHECKS
>
> =A0 =A0 =A0 =A0 If unsure, or if you run an older (pre 4.4) gcc, say N= .
>
> +config PAGE_CACHE_ACCT
> + =A0 =A0 bool "Page cache accounting"
> + =A0 =A0 ---help---
> + =A0 =A0 =A0 Enabling this options to account for page cache hit/miss= ed number of
> + =A0 =A0 =A0 times. This would allow user space applications get bett= er knowledge
> + =A0 =A0 =A0 of underlying page cache system by reading virtual file.= The statitics
> + =A0 =A0 =A0 per partition are collected.
> +
> + =A0 =A0 =A0 If unsure, say N.
> =A0endmenu
> --

rewrite:

=A0 =A0 =A0 =A0 =A0Enable this option to provide for page cache hit/miss c= ounters.
=A0 =A0 =A0 =A0 =A0This allows userspace applications to obtain better kno= wledge of the
=A0 =A0 =A0 =A0 =A0underlying page cache subsystem by reading a virtual fi= le.
=A0 =A0 =A0 =A0 =A0Statistics are collect per partition.

questions:
=A0 =A0 =A0 =A0what virtual file?
=A0 =A0 =A0 =A0what kind of partition?


Hi Ran= dy,

Thanks for your correction.

'virtual file' in th= is patch context means files in sysfs mounted at /sys.
'partition= 9; indicates that every disk partition (like /dev/sda/{sda1,sda2...} has=20 its own accountings for page cache information.

I am not confident about phrasing. so please correct it if you think it= is way better.

Thanks,
Liu Yuan
--20cf305644751d1c2f049d8b61fe-- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org