[CentOS] Finding wich files a writen to

Thu May 5 02:24:10 UTC 2011
Marcelo Beckmann <marcelobeckmann at bsd.com.br>

2011/5/4 Nicolas Ross <rossnick-lists at cybercat.ca>:
> 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...

I sugest a look for tools like this

it helps to make a script to watch file activities, and it uses a kernel feature

I discovered inotify some months ago when I looked into every
initscript in init.d

[23:13:35 root at gw init.d]# cat /etc/redhat-release
CentOS release 5.3 (Final)
[23:13:45 root at gw init.d]# head restorecond
# restorecond:          Daemon used to maintain path file context
# chkconfig:    2345 12 87
# description:  restorecond uses inotify to look for creation of new files \
# listed in the /etc/selinux/restorecond.conf file, and restores the \
# correct security context.

more about inotify:

What Is inotify?

inotify is a file change notification system—a kernel feature that
allows applications to request the monitoring of a set of files
against a list of events. When the event occurs, the application is
notified. To be useful, such a feature must be simple to use,
lightweight with little overhead and flexible. It should be easy to
add new watches and painless to receive notification of events.