Websphere container pool size
 Technote (FAQ)
 
Problem
Questions:
1. What are the beans that the Websphere EJB container pooling apply to?
2. How to configure the container pool size
 
Solution
Q1: What are the beans that the Websphere EJB container pooling apply to?

A1: The Websphere container pooling applies to entity beans and stateless session beans.

Q2: How to configure the container pool size?

A2: There are two ways.


1. The first way is that you can set the maximum and minimum container pool size by configure the System property com.ibm.websphere.ejbcontainer.poolSize. The format you use to set the size of an entity bean or stateless pool is as follows:

beantype=min,max...[:beantype=min,max]

where beantype is the name of the EJB implementation class and min,max are the minimum and maximum pool size parameters for that bean type.

Do not specify the square brackets shown here in the string; they denote optional additional bean types that you can specify after the first one. The delimiter between each new bean type specification is a colon (:). (This is similar to the format of a trace specification string.)

You can specify an asterisk (*) for one of the bean type attributes to indicate that all bean types should use those values unless further overridden by specifying an exact EJB implementation class name somewhere else in the string. To specify that the default value be used, omit either min or max but retain the comma (,) between the two values. If you do not specify a default value with a * bean type, the container defaults of 50 and 500 are used.

For example, suppose you specify the following one-line string (shown here on two lines to improve readability):

com.ibm.ejs.sm.beans.TypeBean=100,200:com.ibm.ejs.sm.tasks.PerformanceTunerBean=54,
:com.ibm.ejs.sm.tasks.RoleAssignmentTaskBean=,300:*=30,100

The string sets the bean pool sizes as follows:

  • com.ibm.ejs.sm.beans.TypeBean will have min=100 and max=200.
  • com.ibm.ejs.sm.tasks.PerformanceTunerBean will have min=54 and max=100 (max comes from the * bean type).
  • com.ibm.ejs.sm.tasks.RoleAssignmentBean will have min=30 and max=300 (min comes from the * bean type).
  • All other beans in the server will have min=30 and max=100.

    You can specify the bean types in the string in any order, including the * bean type.


2. The second way is that you can set the container pool size via administrative console as follows:

Setting the minimum and maximum values on the JVM Settings tab

The easiest place to set this string is on the JVM Settings tab of your application server's properties in the administrative console. To access the tab:

1. Go to the administrative console.
2. Expand Nodes.
3. Expand Application Servers and select your server.
4. Select the JVM Settings tab in the properties view.

To specify the pool size for a bean type in the JVM Settings tab:
1. Under System Properties, click Add.
2. In the dialog that opens, for Name specify com.ibm.websphere.ejbcontainer.poolSize and, for Value, specify beantype=min,max using the format described above. Then, click Apply.

After you add the System property bean pool size, the console will display the resulting -D command-line form of the property specification in the Generated Command Line Arguments box. Also, a message will be written to the standard out file to indicate the pool size for each bean type in the server.

Q3: Is the minumum number (mininum pool size) of instances started at the container startup time ?

A3: The minimum number is not prepopulated at the server startup time, but once the pool does have the minimum number (the beans are inserted into the pool after normal life cycle operations are completed.) The pool will not be drained below the minimum number in normal operations.

 
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > EJB Container
Operating system(s): HP-UX
Software version: 4.0
Software edition:
Reference #: 1081306
IBM Group: Software Group
Modified date: Aug 27, 2003