Portlet load monitoring properties

By setting the portal and portlet configuration parameters, we can monitor the session load and configure the parameters to increase performance.

Portal configuration

After setting the service configuration properties, add the following custom properties for resource environment provider WP ConfigService. These parameters affect all parameters in the portal:

com.ibm.wps.plm.enabled = false

Enable and disable Portlet load monitoring in the portal. By default Portlet load monitoring is disabled. To enable it, set the entry com.ibm.wps.plm.enabled to true in the WAS admin console. If we want to disable Portlet load monitoring, set com.ibm.wps.plm.enabled to false.

com.ibm.wps.plm.statistics.requestnumber = 50

Number of samples for the calculation of the average response time for a portlet. The default value is 50. The average response time for the portlet is calculated from the 50 latest requests that this portlet served. We can change the number of samples used for the average response time calculation. Add an entry with the name com.ibm.wps.plm.statistics.requestnumber to the WAS admin console. Set its value to the number of requests that we want to be used for average response time calculation. For example: To consider the latest 75 requests for the average response time calculation, set the property com.ibm.wps.plm.statistics.requestnumber to a value of 75.

Portlet configuration

Portlet load monitoring can monitor every JSR 168 or JSR 286 portlet installed in the WebSphere Portal. By default, Portlet load monitoring does not monitor portlets. If we want Portlet load monitoring to monitor a portlet, we need to set specific portlet preferences for a portlet definition.

We can configure these portlet preferences for a portlet either by setting them in portlet.xml before deploying the portlet. Or we can administer them after the portlet was deployed using the Manage Portlets administration portlet.

com.ibm.wps.pe.plm.maxrequest

Maximum number of concurrent requests allowed for a portlet. If the number of requests the portlet serves at any time exceeds the maximum number of concurrent requests specified here, then Portlet load monitoring blocks further requests to this portlet. Instead of responding to the requests the portlet renders with a message that states the portlet is not available. To re-enable this portlet for rendering, a portal administrator can enable the portlet using the Manage Portlets administration portlet.

Example: To allow no more than a maximum of 10 concurrent requests for a portlet, set the portlet preference com.ibm.wps.pe.plm.maxrequest to a value of 10.

com.ibm.wps.pe.plm.minrequest

Reactivation limit for a portlet. Use this parameter for a recovery process. If Portlet load monitoring blocked the portlet because it exceeded the maximum number of allowed concurrent requests, then no more requests to this portlet are allowed. If the portlet then completes its active requests after some time, the number of concurrent requests currently served by the portlet decreases. If the number of concurrent requests in the portlet falls back down to the reactivation limit specified for the portlet preference parameter com.ibm.wps.pe.plm.minrequest, Portlet load monitoring enables the portlet for responding to requests and rendering again. This setting is subject to two restrictions:

1. This setting is only evaluated when set the maximum number of concurrent requests using the parameter com.ibm.wps.pe.plm.maxrequest.

2. This value must be less than the maximum number of concurrent requests entereded for the parameter com.ibm.wps.pe.plm.maxrequest.

Example 1: The portlet to respond to requests again when it has no more than three active requests open, set the portlet preference parameter com.ibm.wps.pe.plm.minrequest to 3.

Example 2: If set the maximum number of concurrent requests for a portlet to 10 using the parameter com.ibm.wps.pe.plm.maxrequest and the reactivation limit of concurrent requests for the same portlet to three using the parameter com.ibm.wps.pe.plm.minrequest, Portlet load monitoring works as follows:

1. When the portlet exceeds 10 and reaches 11 concurrent requests, Portlet load monitoring blocks the portlet from further requests.

2. When the portlet completes 8 active requests and has three active requests to complete, Portlet load monitoring allows the portlet to respond to incoming requests again.

com.ibm.wps.pe.plm.average.time.processing

Allowed average response time for the portlet. Set a value in milliseconds. If the portlet exceeds the average response time specified, then Portlet load monitoring blocks further requests to this portlet. To reenable this portlet for rendering, a portal administrator can enable the portlet using the Manage Portlets administration portlet. For example: To specify 3 seconds as the average response time allowed for a portlet, set the portlet preference com.ibm.wps.pe.plm.average.time.processing to 3000 (milliseconds) for this portlet.

Parent Portlet load monitoring for WebSphere Portal

Related tasks:

Set service configuration properties