Ext3 users - May 2002 - ext3 waking hard disk

hi :)

when using ext3, i can't get my hard disks to go to standby mode
any more. i am using timeouts set by hdparm with 2.4.18 kernels.

even when i issue a standby command manually, the disk
spins up again after a few seconds.
however, (to my knowledge) no user space program accessed
this disk at that time.

i suspect ext3's journal to be causing the disk accesses.
is that possible?


sorry if this has already been discussed...

-- 
CU,		  / Friedrich-Alexander University Erlangen, Germany
Martin Waitz	//  [Tali on IRCnet]  [tali.home.pages.de] _________
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dies ist eine manuell generierte mail, sie beinhaltet    //
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noch Sicherheit verdient.
			Benjamin Franklin  (1706 - 1790)

On Mon, 6 May 2002, Martin Waitz wrote:
> hi :)
>
> when using ext3, i can't get my hard disks to go to standby mode
> any more. i am using timeouts set by hdparm with 2.4.18 kernels.
>
> even when i issue a standby command manually, the disk
> spins up again after a few seconds.
> however, (to my knowledge) no user space program accessed
> this disk at that time.
>
> i suspect ext3's journal to be causing the disk accesses.
> is that possible?
Have you mounted all partitions on this disk with the "noatime"
option?
When not every (readonly) file access gets stored back on the disk
(updates the file inode to reflect the latest atime). Afaik ext3 shouldn't
write anything to the disk when the journal doesn't get hit.

best regards,
michael

On Mon, May 06, 2002 at 01:28:03PM +0200, Michael Renner
wrote:
> Have you mounted all partitions on this disk with the "noatime"
option?
they are mounted "rw,noatime,nodiratime"

-- 
CU,		  / Friedrich-Alexander University Erlangen, Germany
Martin Waitz	//  [Tali on IRCnet]  [tali.home.pages.de] _________
______________/// - - - - - - - - - - - - - - - - - - - - ///
dies ist eine manuell generierte mail, sie beinhaltet    //
tippfehler und ist auch ohne grossbuchstaben gueltig.   /
			    -
Wer bereit ist, grundlegende Freiheiten aufzugeben, um sich 
kurzfristige Sicherheit zu verschaffen, der hat weder Freiheit 
noch Sicherheit verdient.
			Benjamin Franklin  (1706 - 1790)

Hi,

On Mon, May 06, 2002 at 12:16:44PM +0200, Martin Waitz
wrote:
> 
> when using ext3, i can't get my hard disks to go to standby mode
> any more. i am using timeouts set by hdparm with 2.4.18 kernels.
Hmm, I've no idea --- it works fine for me.
> i suspect ext3's journal to be causing the disk accesses.
> is that possible?
The journal shouldn't be active unless there is data queued for write
to the disk.

Cheers,
 Stephen

On Mon, 2002-05-06 at 12:16, Martin Waitz wrote:
> hi :)
> 
> when using ext3, i can't get my hard disks to go to standby mode
> any more. i am using timeouts set by hdparm with 2.4.18 kernels.
> 
> even when i issue a standby command manually, the disk
> spins up again after a few seconds.
> however, (to my knowledge) no user space program accessed
> this disk at that time.
> 
> i suspect ext3's journal to be causing the disk accesses.
> is that possible?
> 
> 
Maybe you have something writing to the disk behind your back. I
experienced this with process accouting. When turned on the kernel will
write data to a file (/var/log/pacct) periodically. On redhat 7.2
machines process accouting is enabled at boot time if the "psacct"
package is installed. Just uninstall that package. You might also have
some other things running and writing data from cron, like the systat
package. Note that ext3 will only wait 5 seconds with dirty data to be
written to disk.
> sorry if this has already been discussed...
> 
> -- 
> CU,		  / Friedrich-Alexander University Erlangen, Germany
> Martin Waitz	//  [Tali on IRCnet]  [tali.home.pages.de] _________
> ______________/// - - - - - - - - - - - - - - - - - - - - ///
> dies ist eine manuell generierte mail, sie beinhaltet    //
> tippfehler und ist auch ohne grossbuchstaben gueltig.   /
> 			    -
> Wer bereit ist, grundlegende Freiheiten aufzugeben, um sich 
> kurzfristige Sicherheit zu verschaffen, der hat weder Freiheit 
> noch Sicherheit verdient.
> 			Benjamin Franklin  (1706 - 1790)
-- 
-------------------------------------------------------
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