Disk chatter every 5 seconds

[Scott J. Henson]

Daniel Allen wrote:

>Ubuntu (5.04 and 5.10) seem to run a device-related daemon (HALd?
>udev?) which makes the disk activate in a short burst exactly every 5
>seconds.  Since the disk is the loudest part of my home system, the
>pattern is sometimes a bit distracting.
>
>Anybody know what's the cause, and whether it's configurable behavior?
> I have done a bit of poking, but I haven't been able to isolate it,
>beyond that it doesn't happen in runlevel 2, and it doesn't stay
>active long enough to show up in 'top'.
>  
>
That 5 seconds sounds an aweful lot like the 5 second commit interval 
that ext3fs has.  So its not hald or udev directly.  Its probably 
something doing some logging or something else.  You may also think your 
not writting anything to disk, but every you access a file the atime 
must be updated, so that needs to be written to disk.  On my laptop I 
set the noatime option on all my partitions.  This will keep it from 
updating that.  Also you should check in /var/log to see if anything is 
writting too much to disk and see if you can scilence it.  Generally 
setting the noatime mount option fixes it.  You can set this in 
/etc/fstab.  Man mount for a full description of this option.