Hi,

To be able to have 100 000 files open systemwide is not so strange...

There are two types of limit of the max. number of file descriptors: system-wide and login shell-wide. The system-wide can be checked this way:
cat /proc/sys/fs/file-max
The default value is 205290 on many distros.

The other limit is per user and per login shell and is set in /etc/security/limits.conf in CentOS and openSUSE. The default value for that is 1024. This means when you log in and run 'ulimit -n' from your shell it shows 1024. There is a way to set it higher:

/etc/iniscript:
ulimit -n 4096
eval exec "$4"

/etc/security/limits.conf
* soft nofile 1024
* hard nofile 1024
root soft nofile 4096
root hard nofile 8192
user1 soft nofile 4096
user1 hard nofile 8192

Here is a reference:
http://publib.boulder.ibm.com/infocenter/dmndhelp/v6rxmx/index.jsp?topic...

and another one:
http://confluence.atlassian.com/display/CONF26/Fix+%27Too+many+open+file...

HTH