IBM 6.1.X Web Server Tuning, KeepAliveTimeout, ThreadsPerChild, MaxRequestsPerChild, StartServers

Web Server Tuning

We used IBM HTTP Server 6.1 in our measurement environment. The cluster configuration and the Solaris configuration has a remote web server, find the tuning in Web Server Tuning in Cluster Tuning section. All other configurations have the web server running on the same system as the WebSphere Portal application server. If, during your monitoring, you notice insufficient processor capacity on the system when running the web server and the portal application server on a single system, consider separating the servers onto different systems. We used the following tuning on our web servers:

Table 10: Web Server Tuning

Parameter	AIX	Linux	Windows	z/Linux	Additional Information
	POWER5		2003
KeepAliveTimeout	5	5	5	5	This value is less than the think
					time defined in our scripts to
					ensure that testing is
					conservative. Each user is
					assumed to open a new TCP
					connection for each page view.
					However, in a live environment, it
					can be helpful to increase the
					KeepAlive Timeout. A higher
					timeout value can increase
					contention for HTTP server
					processes, if you are running out
					of HTTP processes, decrease
					this value.
ThreadsPerChild	25	25	2000	25	The higher number of threads per
					child on Windows is due to a
					different process model for IHS
					on Windows.
MaxKeepAliveRequests	0	0	0	0	Selecting 0 lets an unlimited
					number of requests on a single
					TCP connection.
MaxRequestsPerChild	0	0	0	0
StartServers	2	2	N/A	2
Access logging	off	off	off	off	This was turned off by
					commenting out the following
					configuration line:
					CustomLog
					/usr/HTTPServer/logs/access_log
					common
ThreadLimit	25	25	2000	25
ServerLimit	150	120	N/A	180	Set it
		2 3

W E BS P HE R E P O R T AL V 6 . 1 T U N I N G G U I D E