General Information for an OpenVMS Installation

In this section:

This section covers general information for an OpenVMS Installation.


Top of page

x
Java Listener JVM Defaults

How to:

The Java Listener on OpenVMS Alpha has pre-set values for Initial Java Heap Size (JVM_INIT_HEAP) and Maximum Java Heap Size (JVM_MAX_HEAP) because the internal Java defaults for these values are insufficient (and cause features to fail). Plus, the OpenVMS Alpha Java documentation explicitly states that the internal defaults should not be depended on.

The pre-set values do not reflect any tuning, but are simply known working values. Specific tuning should be done based on your application need. Java’s own internal default for this heap size is insufficient and in-turn causes server features to fail. The pre-set value does not reflect any specific tuning, but is simply a known working value. Specific tuning should be done based on application need.

Since OpenVMS Integrity (IA64) Java does not have issues with these internal defaults, they are not pre-set. However, applications may benefit from specific tuning.



x
Procedure: How to Tune the Java Listener from the Web Console

To tune the Java Listener from the Web Console:

  1. Select Workspace from the menu bar.
  2. Open the Java Services folder.
  3. Right-click DEFAULT and select Properties.

    The Java Services Configuration pane opens.

  4. Expand the JVM Settings section.
  5. Under Non-standard JVM options, enter values in the Initial Java Heap Size and Maximum Java Heap Size fields.
  6. Click Save and Restart Java Services.

Top of page

x
Configuring for IEEE/G_FLOAT Float Data

As of 7.7.02, OpenVMS 8.x builds are natively IEEE builds and the SET VMSFLOATCONV = IEEE/G-FLOAT command is used to SET the float read method for single (F)/double (D) float data. This requires separate server configurations for each float type and a hub-sub arrangement to join data By default, an IEEE build needs no explicit SET command to access IEEE float data, although it is allowed. To access G_FLOAT data, the following command must be added to the server edasprof.prf:

SET VMSFLOATCONV = G-FLOAT

This may be done from the Web Console using the server profile edit feature.

The SET command is ignored on non-applicable platforms, so application sources may be shared. The setting also does not apply to the OpenVMS 7.x builds, which are strictly G_FLOAT builds.


iWay Software