2.6: XFS spins up the disk very often

[Ricardo Galli <gallir@uib.es>]

Hi,

	since I started with 2.5 in my laptop, I noticed that the disk with XFS was 
spinning up continously. I checked with vmstats, and I saw I/O almost every 
60 seconds. They were mainly outputs, among 11 and 250 blocks each time.

I checked every process and redirected all syslogd to /dev/tty7 to be sure no 
processes were generating the I/O. I couldn't find any.

So finally I repartitioned the disk and copied the whole system to a XFS 
partition and to an Ext3. Then I tested both, rebooting each time and 
changing the root fs.

With Ext3 there is no problem, the disk spins off very rapidly, but XFS kept 
doing I/O's.

So I checked it again in 2.4.21-ac4. Although there were more XFS I/O than 
with Ext3, they were not so frequent as in 2.6.

I also played echoing different values to /proc/sys/fs/xfs/ and 
/proc/sys/vm/pagebuf/ files without noticeable changes.

Is it a problem in 2.6 or the /proc parameters must be fine tuned?


-- 
  ricardo galli       GPG id C8114D34
  http://mnm.uib.es/~gallir/