From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.technolabs.it (host20-155-static.82-213-b.business.telecomitalia.it [213.82.155.20]) by ozlabs.org (Postfix) with ESMTP id 704C2DDE39 for ; Sat, 19 Jan 2008 00:15:07 +1100 (EST) MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C859D4.22D22F3E" Subject: A file of 5 MB on tmpfs file system uses 5 MB of RAM or more? Date: Fri, 18 Jan 2008 14:15:02 +0100 Message-ID: From: "DI BACCO ANTONIO - technolabs" To: List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This is a multi-part message in MIME format. ------_=_NextPart_001_01C859D4.22D22F3E Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable I have a linux-2.6.19.2 board with an MPC880 with 16MB ram and 16 MB flash.=20 Normally I have 9-10 MB of free RAM. =20 If I allocate 5 MB of ram memory, the system continues to work normally, but if, instead of allocating 5 MB directly, I fill the /tmp directory (that has a tmpfs file system) with a 5MB file the system becomes slow and after some minutes the oom_killer is invoked. Before it dies I had the time to see that mtdblockd is taking a lot of CPU (20%), what could be the problem? =20 Any hint will be appreciate, Bye, Antonio. ------_=_NextPart_001_01C859D4.22D22F3E Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable
I have = a=20 linux-2.6.19.2 board with an MPC880 with 16MB ram and 16 MB flash.=20
Normally I have 9-10=20 MB of free RAM.
 
If I = allocate 5 MB=20 of ram memory, the system continues to work normally, but if, instead of = allocating 5 MB directly, I fill the /tmp directory (that has a = tmpfs file=20 system) with a 5MB file the system becomes slow and after some minutes = the=20 oom_killer is invoked. Before it dies I had the time to see that = mtdblockd is=20 taking a lot of CPU (20%), what could be the = problem?
 
Any = hint will be=20 appreciate,
Bye,
Antonio.
------_=_NextPart_001_01C859D4.22D22F3E-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 54D10DDED3 for ; Sat, 19 Jan 2008 02:51:02 +1100 (EST) Message-Id: <1C05D4DF-8C6A-4EFD-96F4-07FC75241970@kernel.crashing.org> From: Kumar Gala To: DI BACCO ANTONIO - technolabs In-Reply-To: Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Mime-Version: 1.0 (Apple Message framework v915) Subject: Re: A file of 5 MB on tmpfs file system uses 5 MB of RAM or more? Date: Fri, 18 Jan 2008 09:50:54 -0600 References: Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Jan 18, 2008, at 7:15 AM, DI BACCO ANTONIO - technolabs wrote: > I have a linux-2.6.19.2 board with an MPC880 with 16MB ram and 16 MB > flash. > Normally I have 9-10 MB of free RAM. > > If I allocate 5 MB of ram memory, the system continues to work > normally, but if, instead of allocating 5 MB directly, I fill the / > tmp directory (that has a tmpfs file system) with a 5MB file the > system becomes slow and after some minutes the oom_killer is > invoked. Before it dies I had the time to see that mtdblockd is > taking a lot of CPU (20%), what could be the problem? > Posting any output from OOM, etc would be useful. - k From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from de01egw01.freescale.net (de01egw01.freescale.net [192.88.165.102]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "de01egw01.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 3B917DDF7F for ; Sat, 19 Jan 2008 02:59:04 +1100 (EST) Date: Fri, 18 Jan 2008 09:58:53 -0600 From: Scott Wood To: DI BACCO ANTONIO - technolabs Subject: Re: A file of 5 MB on tmpfs file system uses 5 MB of RAM or more? Message-ID: <20080118155853.GA15620@ld0162-tx32.am.freescale.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Jan 18, 2008 at 02:15:02PM +0100, DI BACCO ANTONIO - technolabs wrote: > I have a linux-2.6.19.2 board with an MPC880 with 16MB ram and 16 MB > flash. > Normally I have 9-10 MB of free RAM. > > If I allocate 5 MB of ram memory, the system continues to work normally, Are you sure the RAM was actually allocated (i.e. did you write to all of the pages)? -Scott From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.technolabs.it (host20-155-static.82-213-b.business.telecomitalia.it [213.82.155.20]) by ozlabs.org (Postfix) with ESMTP id 0BBA6DDEEE for ; Sat, 19 Jan 2008 09:24:50 +1100 (EST) MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C85A20.EFCE0116" Subject: RE: A file of 5 MB on tmpfs file system uses 5 MB of RAM or more? Date: Fri, 18 Jan 2008 23:23:20 +0100 Message-ID: References: <20080118155853.GA15620@ld0162-tx32.am.freescale.net> From: "DI BACCO ANTONIO - technolabs" To: "Scott Wood" Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This is a multi-part message in MIME format. ------_=_NextPart_001_01C85A20.EFCE0116 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable No I simply did several malloc(s) without writing to the allocated = space. This means that the pages are not allocated really? -----Original Message----- From: Scott Wood [mailto:scottwood@freescale.com] Sent: Fri 18/01/2008 16.58 To: DI BACCO ANTONIO - technolabs Cc: linuxppc-embedded@ozlabs.org Subject: Re: A file of 5 MB on tmpfs file system uses 5 MB of RAM or = more? =20 On Fri, Jan 18, 2008 at 02:15:02PM +0100, DI BACCO ANTONIO - technolabs = wrote: > I have a linux-2.6.19.2 board with an MPC880 with 16MB ram and 16 MB > flash.=20 > Normally I have 9-10 MB of free RAM. > =20 > If I allocate 5 MB of ram memory, the system continues to work = normally, Are you sure the RAM was actually allocated (i.e. did you write to all = of the pages)? -Scott ------_=_NextPart_001_01C85A20.EFCE0116 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable RE: A file of 5 MB on tmpfs file system uses 5 MB of RAM or = more?

No I simply did several malloc(s) without writing to = the allocated space.

This means that the pages are not allocated really?



-----Original Message-----
From: Scott Wood [mailto:scottwood@freescale.com]
Sent: Fri 18/01/2008 16.58
To: DI BACCO ANTONIO - technolabs
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: A file of 5 MB on tmpfs file system uses 5 MB of RAM or = more?

On Fri, Jan 18, 2008 at 02:15:02PM +0100, DI BACCO ANTONIO - technolabs = wrote:
> I have a linux-2.6.19.2 board with an MPC880 with 16MB ram and 16 = MB
> flash.
> Normally I have 9-10 MB of free RAM.
> 
> If I allocate 5 MB of ram memory, the system continues to work = normally,

Are you sure the RAM was actually allocated (i.e. did you write to all = of
the pages)?

-Scott

------_=_NextPart_001_01C85A20.EFCE0116-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw01.freescale.net (az33egw01.freescale.net [192.88.158.102]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw01.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 4A4DBDDF13 for ; Sat, 19 Jan 2008 09:25:25 +1100 (EST) Message-ID: <47912763.8090106@freescale.com> Date: Fri, 18 Jan 2008 16:25:39 -0600 From: Scott Wood MIME-Version: 1.0 To: DI BACCO ANTONIO - technolabs Subject: Re: A file of 5 MB on tmpfs file system uses 5 MB of RAM or more? References: <20080118155853.GA15620@ld0162-tx32.am.freescale.net> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , DI BACCO ANTONIO - technolabs wrote: > No I simply did several malloc(s) without writing to the allocated space. > > This means that the pages are not allocated really? Correct. -Scott