Web Performance Advisor

The Web Performance Advisor provides a way to view, evaluate and modify the attributes that affect the performance of your Web environment. Clear definitions of the attributes are provided along with recommended values. The tool also provides rating for each attribute to help guide the user to acceptable settings.

A Web environment is a grouping of related Web and application servers that form a Web solution. A Web environment is typically made up of a single WebSphere® Application Server instance or profile and all the application servers contained within, its corresponding IBM® HTTP Server, and any system attributes that could have a direct effect on the performance of the Web environment.

The Web Performance Advisor is made up of multiple components to help you tune the performance of your system and Web environment. These components include an advisor and an export function. These can be launched from the Web Performance Advisor introduction page. On this introduction page, the user is provided a quick, easy-to-read, high-level view of their system and Web environment performance.

The Advisor function allows you to manage system attributes and to manage Web environment attributes. From the manage system and manage Web environment panels, you can view, evaluate, and change each performance attribute. While evaluating each performance attribute, click the attribute's Advise link to learn about the attribute and find the recommended setting. The Web Performance Advisor gathers ratings and recommendations for each of the performance attributes being tuned. From these ratings, icons are displayed to convey whether the attribute is tuned well (green), may need some additional tuning (yellow), or needs immediate attention (red). The ratings that are displayed may vary based on the risk level (conservative or aggressive) you have configured in the General Settings. Conservative means that you do not want to be alerted to those performance attributes that are on the fringe. By using the conservative approach, fewer attributes are changed and drastic performance updates are not made. Of course, performance may not be tuned as well, but there is much less risk of degrading your machine as a whole. Using the aggressive approach, any attribute that is on the fringe is flagged as needing to be changed. In addition, attributes that would be flagged as good in a conservative mode, might actually be flagged as needing improvement. By doing this, more drastic performance updates are made which may dramatically improve performance. On the downside, the possibility exists that unexpected, unwanted consequences may result from these drastic performance changes.

The export function allows you to save existing performance settings in a performance profile. This profile can be evaluated, compared, or sent to a performance expert for analysis and modification.

When the Web Performance Advisor tool is used to examine a Web related server, a flight recorder performance profile is created to save what all performance attributes are set to prior to any changes being made. Whenever changes are made through the Web Performance Advisor, all the performance attributes are saved (including the new changes) to another flight recorder performance profile file. This is necessary so that you can keep track of all changes made to a Web environment. All flight recorder performance profile files are located in the '/QIBM/UserData/HTTPA/admin/WPA' directory. The Web Performance Advisor tool does not clean up these files; they remain until someone deletes them manually.