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 application server, its corresponding IBM® HTTP Server for i Web server, and any system attributes that could have a direct effect on the performance of the Web environment. Supported application servers include WebSphere® Application Server, Integrated Web Application Server for i, and the Integrated Web Services Server for i.
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 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.
- System attribute information made up of the physical and logical resources that have been allocated to the system and partition and selected system values that can have a direct effect on Web performance, TCP/IP settings, and PTF information including the PTF Groups and the individual product PTFs for the products that are used in a Web environment.
- Web attribute information for an application server.
- Web performance attributes for an application server, including the JVM settings, system and server resource settings, server JDBC providers and data source resources, and other additional server settings.
- Web attribute information related to your external HTTP server that is associated with the application server.
Details
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.
Prerequisites and assumptions
The Web Performance Advisor feature supports a wide variety of WebSphere and non-WebSphere products. These include WebSphere Application Server, WebSphere Portal Server, Integrated Application Server, and the Integrated Web Services Server. The other product that is supported is the IBM HTTP Server for i Web server when it is configured to be used by one of the previously listed products.
- WebSphere Application Server V7 (Base and Express® editions and Network Deployment in a stand-alone environment)
- WebSphere Application Server V6.1 (Base and Express editions and Network Deployment in a stand-alone environment)
- WebSphere Portal V6.1.5
Start the Web Performance Advisor
- Access the Web Administration for i from your browser. For information about how to access the Web Administration for i interface, see Starting Web Administration for i.
- From the IBM Web Administration for i interface, select the server you want to examine.
- In the navigation pane, expand Web Performance,
and select Web Performance Advisor. Note: If Web Performance Advisor is not displayed in the navigation pane, either you need to install the latest HTTP Server group PTF, or the selected server is not supported by the Web Performance Advisor.
The Web Performance Advisor introduction page displays. From this page, you can select to manage your system or your Web attributes, change your general settings, or export your current performance settings.
More performance tuning tools
The Web Performance Advisor is only one tool available for you to tune your performance settings. The Web Performance Advisor, the Workload Estimator, and the documented minimums are all tools available to help you achieve improved performance. These resources can be used together to find the settings that are best for you.
Documented minimums: This is the smallest possible system you should run on. These systems may be appropriate for development or internal systems with a small number of users where longer response times are acceptable. Good performance is not expected on these systems.
Workload Estimator: This tool accounts for the specific characteristics of your workload to recommend an appropriate system. It should be used to determine the size and type of system that should be used based on the type of workloads you plan on running. It cannot recommend a system that is smaller than the documented minimum recommendations, but it may recommend a larger system.
Web Performance Advisor: This tool is recommended if you are trying to get good performance out of your applications and environment. It may recommend configurations that are somewhat larger than the documented minimums. The recommendations could, however, be smaller than the Workload Estimator recommendations, because the Web Performance Advisor does not account for the specific workload your system faces during the runtime of your applications or other things that may be running on your system.