HI All,

Can any one advise based on experience:

We are load balancing weblogic and Tomcat traffic with hundreds of backend servers/applications and simple URI rewrites.
We are considering whether to have several hundred simple rules for each application/server or much fewer bigger rules with switch statements for each application. Individual rules seem better for troubleshooting but use up so many VIPs. Just wondering which is better for performance.

Thanks -ML

Without knowing the exact requirements, it's hard to give an exact suggestion. You could try doing some simple load testing with the VIP configured with a single iRule and compare that performance with many small iRules. This should give you the most definitive answer for which approach is more efficient.

Administratively I think it would be simpler to combine similar functions into the same iRule. If you have a lot of rewrites to do, it would probably be more efficient to add them all to the same datagroup and use matchclass (v9 or 10)/findclass (v9 or 10)/class (v10) to determine which rewrite to perform compared with many small iRules.

Also, you can post questions like this to the iRules discussion group to get more relevant views on your post:
http://devcentral.f5.com/Community/GroupDetails/tabid/1082223/asg/50/aff/5/afv/topicsview/showtab/groupforums/Default.aspx

Aaron

Thanks, Aaron.

And, don't forget, there is a section in the iRules forum for Optimizing iRule Performance, with an Excel spreadsheet calculator to help analize your iRules.

http://devcentral.f5.com/Tutorials/TechTips/tabid/63/articleType/ArticleView/articleId/123/iRules-Optimization-101--05--Evaluating-iRule-Performance.aspx

-Chris.