IBM G210-1784-00 manual Tuning HTTP servers, Sun Solaris servers, tcptimewaitinterval

Sun Solaris servers

Adjust the following TCP/IP parameters to tune performance in Solaris:

tcp_time_wait_interval

This parameter tells Solaris how long in milliseconds to keep a socket that was closed before releasing it for re-use.

Recommended value: 30000 (= 30 seconds)

To see the current value, use this command:

/usr/sbin/ndd –get /dev/tcp tcp_time_wait_interval

To change the value, use this command:

/usr/sbin/ndd -set /dev/tcp tcp_time_wait_interval 30000

tcp_fin_wait_2_flush_interval

This parameter defines how many milliseconds to wait for a final FIN packet (state of FIN_WAIT_2) before the socket is forcibly closed.

Recommended value 67500 (= 67,5 seconds)

To see the value, use this command:

/usr/bin/ndd -get /dev/tcp tcp_fin_wait_2_flush_interval

To change the value, use this command:

/usr/bin/ndd -set /dev/tcp tcp_fin_wait_2_flush_interval 67500

tcp_keepalive_interval

This parameter defines the timer interval in milliseconds prohibiting an active connection from staying established if one of the peers never responds.

Recommended value: 300000 (= 300 seconds)

To see the value, use this command:

/usr/bin/ndd -get /dev/tcp tcp_keepalive_interval

To change the value, use this command:

/usr/bin/ndd -set /dev/tcp tcp_keepalive_interval 300000

Tuning HTTP servers

Depending on the expected number of concurrent users, you may have to change some settings in the configuration of the HTTP servers you are utilizing within your LMS configuration. Use the following guidelines for tuning HTTP servers.

Adjusting the reload interval for the WebSphere plug-in configuration file

Every 60 seconds, by default, the WebSphere plug-in reloads its configuration file (plug-in.xml) to check if any changes occurred. The dynamic regeneration of this configuration information is costly in terms of performance. Therefore, in production environments you should change the <RefreshInterval=xxxx> parameter defined in the configuration file itself to a higher value.

Appendix A: LMS Performance and Fine-tuning Information 109