Technical Notes

This technical note explains how to configure options for recording model debug messages on the Session Server.

This technical note is organized into the following sections:

Understanding Model Debug Messages

The Model Debug Messages feature records activity of your Verastream model interacting with the host application, providing the detail that is sometimes necessary to diagnose and repair a malfunctioning model. This feature is particularly helpful for model designers working with VT (UNIX or OpenVMS) or HP hosts, where synchronization and related timeout issues are more common.

The Design Tool always records model debug messages. The Session Server can also be configured to record model debug messages at runtime, as described in this technical note. This feature uses a dedicated memory cache to maintain fast performance of the server.

After recording your problem, see Technical Note 10065 for information on using the recorded model debug messages (.vmr) files in Design Tool.

Configuring Recording Level for a Development or Test Server

To configure the recording level for models deployed from the Design Tool to a local or test Session Server, click:

Choose one of the following options:

Configuring Recording Level in a Deployment Descriptor

For models being deployed to a production Session Server, you can set the model debug messages recording level in the deployment descriptor (prior to running packagemodel and activatemodel commands).

In your configuration descriptor XML file, define the recording level in the model-configuration section as follows:

Note: The recording-mode information must be located after host-port (otherwise the packagemodel command will fail). For example:

Model configurations are referenced by session pool configurations and/or deployment targets. For more information on writing deployment descriptors, see Technical Note 10237.

Configuring Recording Options in Administrative WebStation

To view or change the model debug message recording options in Administrative WebStation, open the Administrative WebStation console and log in.

If you are in View mode, you can view configuration information, but you cannot modify it. If you are logged on using the Administrator profile, you can switch to Config mode and modify configurations.

Checking the Recording Level

Use the following steps to view or change the Model Debug Message Recording level for a model or session pool.

Note: If you change the model configuration or session pool configuration in Administrative WebStation, it will be overwritten by subsequent deployment from Design Tool or by the activatemodel command.

1. In the Administrative WebStation, click Host Integrator Setup > Servers > [server name] > Server Configuration.
2. The Model Debug Message Recording option is located on the following pages:

Model Debug Message Recording options are:

Managing the Size and Location for Recorded Files

To manage the size and location of the model debug message files recorded by the runtime Session Server, click:

Model Debug Messages Directory

By default, the <vhi>/etc/reports directory is used for storing model debug messages subdirectories and files, where <vhi> is the Verastream Host Integrator installation directory. This folder contains subdirectories corresponding to the time the Session Server started. The time-stamped directory contains model debug message files (with .vmr extension) typically named by model name and session ID, for example, CICSAccts.8.vmr (see also Technical Note 10065 for file naming details).

If desired, you can change the directory value to a different location on the local system.

Note: Changing the setting for the directory will not take effect until the server is restarted.

Model Debug Messages Cache Size

This option sets the size of the memory buffer for model debug messages. The default cache size is 500 KB. When the buffer is filled with recorded activity, its contents are written to the model debug messages .vmr file. The model debug message recording process continues, and additional messages are added to the file when appropriate.

Each session uses its own cache. If you find that model debug message recording is slowing down the server, or you have ample physical memory installed, you may want to increase this value to reduce the frequency of writing to disk.

Model Debug Message Time Threshold

This option sets amount of time that a model debug message .vmr file remains on the server. Periodically, any files older than the setting specified here will be removed, regardless of disk space availability. The default is 7 days. If this time threshold is set to 0 days, it is disabled (files are kept forever, or until the space threshold is reached).

The time threshold is applied on a daily basis (or on an hourly basis if the space threshold is enabled).

Model Debug Message Space Threshold

This option sets the amount of disk space, in MB, that is maintained for the most recent model debug message .vmr files. The model debug message directory is reduced to this size on an hourly basis, keeping the newest files that fit within this threshold. The reduction process removes oldest files when necessary.

By default, this space threshold is disabled (set to 0 MB), so only the time threshold applies.

Since the space threshold is only applied on an hourly basis, if you want to strictly enforce a maximum space for model debug message space, it is recommended that you specify a dedicated virtual drive on the local machine as the Model Debug Messages Directory.