[CentOS] Finding wich files a writen to

Hi !

I have a server (Centos 5) that is using a pair of SAS drives to store the data. (Mail server) They are on an adaptec raid controler with a battery backup and write back cache active.

From time to time, I have sever peak io to those data disks (> 400 to 500

iops, > 70 to 100 megs/sec).

With iostat, I find that it's almost a write i/o problem. How can I find to which files the OS writes ? On OSX boxes, there is a utility called fs_usage that can reports any disk activity for a particular process or all processes. Is there any utility like this on Centos ?

iotop can points me to wich process, but that doesn't points me to what files are the culprits...