Chapter 2 Server Tuning

Factors that affect start-up and shutdown time

These settings affect how long it takes to shut down and restart the server.

Start-up performance

These settings affect how long it takes the server to start, that is, the time between starting the process and when the server is ready to accept connections:

Random number seeding EAServer uses encryption algorithms that generate pseudorandom number generation. EAServer generates a random seed at start-up by collecting a variety of data from system sources. On some machines, the default seeding mechanism can cause start-up lag times. You can change the seeding mechanism as described in "Setting the JAGUAR_RANDOMSEED variable" in the EAServer System Administration Guide.
Message service initialization If you are running the message service, it must initialize before the server can accept connections. At start-up, the message service reads unprocessed persistent messages into the in-memory cache. A large message backlog can delay server start-up. To control the number of messages read into memory, set the default.maximum property for the message service, as described in "Other global settings".
Service components All service components must return from their start methods before EAServer accepts client connections. Lengthy processing in the start method can delay server start-up. For more information, see Chapter 33, "Creating Service Components," in the EAServer Programmer's Guide.
JSPs loaded at start-up JSPs that are configured to load at start-up are compiled if necessary. Compilation of many JSPs can delay start-up. You can reduce JSP compilation time by tuning the Web application settings discussed in "Runtime compilation settings".
Servlets loaded at start-up Servlets that are configured to load at start-up must return from their init method before the server continues. Lengthy processing in this method can delay start-up. (If the servlet does not load at start-up, lengthy processing in this method can delay the response to the first client request). You can set a time limit for servlet initialization to complete by setting these properties:
- For the server, the Timeout setting on the Servlets tab in the EAServer Manager Server Properties dialog box specifies an initialization timeout for servlets that are installed directly in the server. You can also set this property as com.sybase.jaguar.server.servlet.init-timeout using jagtool.
- For the Web application, the Timeout setting on the General tab in the EAServer Manager Web Application Properties dialog box specifies an initialization timeout for servlets in the Web application. You can also set this property as com.sybase.jaguar.webapplication.init-timeout using jagtool.
- For individual servlets, the com.sybase.jaguar.servlet.init.timeout property, set using jagtool or on the Advanced tab in the EAServer Manager Web Component or Servlet Properties dialog box.
To specify a timeout, set the property to a positive integer, which specifies the number of seconds to wait. The default is 0, which indicates that there is no time limit.

Shutdown performance

These settings affect how long it takes the server to shut down.

Pooled component destruction

EAServer explicitly destroys pooled component instances before the server shuts down. This allows you to perform cleanup operations in your component, such as closing database connections. You can set the following server and component properties to change this behavior:

com.sybase.jaguar.server.destroyPooledInstancesOnShutdown for the server specifies whether to destroy pooled component instances when shutting down. A value of true indicates that pooled instances must be destroyed explicitly before shutting down. For example, an EJB component's ejbRemove method is called. This allows the pooled instance to clean up resources, such as closing database connections. A value of false specifies that instances are not destroyed. The default is true .

If many component instances are pooled, explicit destruction of instances may lengthen the time required to shut down or restart the server.

You can override the setting for individual components by setting the com.sybase.jaguar.component.destroyPooledInstancesOnShutdown component property.
com.sybase.jaguar.server.destroyPooledInstancesOnShutdownTimeout for the server specifies how long to wait for each instance destruction method to return when destroying pooled instances during server shutdown. The value specifies the time to wait, in seconds. If no value is specified, the default is 5. You can override the setting for individual components by setting the component property com.sybase.jaguar.component.destroyPooledInstancesOnShutdownTimeout.

Set these properties on the Advanced tab in the Server Properties or Component Properties dialog boxes.

Servlet destruction

EAServer calls each servlet's destroy method before shutting down or after you have refreshed or stopped the servlet using EAServer Manager. If service calls are still active, the Destroy Timeout setting specifies the number of seconds that the server should wait for the service calls to return before calling the destroy method. The default behavior specifies that the server wait indefinitely for service calls to return. You can specify a finite timeout by setting these properties:

For the server, the Destroy Timeout setting on the Servlets tab in the EAServer Manager Server Properties dialog box specifies a timeout for servlets that are installed directly in the server. You can also set this property as com.sybase.jaguar.server.servlet.destroy-wait-time using jagtool.
For the Web application, the Destroy Timeout setting on the General tab in the EAServer Web Application Properties dialog box specifies a timeout for servlets in the Web application. You can also set this property as com.sybase.jaguar.webapplication.destroy-wait-time using jagtool.
For individual servlets, the com.sybase.jaguar.servlet.destroy.wait-time property, set using jagtool or on the Advanced tab in the EAServer Manager Web Component Properties dialog box.

To specify a timeout, set the property to a positive integer, which specifies the number of seconds to wait. The default is 0, which specifies that EAServer calls destroy immediately.