Sun Java System Application Server 9.1 Performance Tuning Guide

File Descriptor Setting

On the Solaris OS, setting the maximum number of open files property using ulimit has the biggest impact on efforts to support the maximum number of RMI/IIOP clients.

To increase the hard limit, add the following command to /etc/system and reboot it once:

set rlim_fd_max = 8192

Verify this hard limit by using the following command:

ulimit -a -H

Once the above hard limit is set, increase the value of this property explicitly (up to this limit) using the following command:

ulimit -n 8192

Verify this limit by using the following command:

ulimit -a

For example, with the default ulimit of 64, a simple test driver can support only 25 concurrent clients, but with ulimit set to 8192, the same test driver can support 120 concurrent clients. The test driver spawned multiple threads, each of which performed a JNDI lookup and repeatedly called the same business method with a think (delay) time of 500ms between business method calls, exchanging data of about 100KB. These settings apply to RMI/IIOP clients on the Solaris OS.

For more information about setting file descriptor limits, see the following documentation for the Solaris OS:

For information about the /etc/system file, see the system(4) man page.