Just as the subject says:

I have a scsi hdd with 4 reiserfs partitions on it.

Has I was interested in finding out about the utilisation of the hdd (when I gets to work) I installed iostat to give me some numbers every 5 minutes.

I was supprised but as the Server is not being accessed by anybody I suggested the utilisation to be 0 but every day at about 4 o clock the utilisation goes up to nearly 90 % and stays there for about 10 minutes.

What is that ?

I checked the cron jobs but there is nothing starting at that point of time.

Is reiser checking itself?

Thanks for your help!