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Embedding Informix®
When you embed HCL Informix®, you can use enterprise-class high-availability and high performance with embeddability features such as easy programmability, a small disk and memory footprint, and silent deployment.
Embedding HCL Informix®
The Informix® Embeddability Guide describes how to embed HCL Informix in your applications.
Manage memory in embedded environments
You can manage memory in embedded environments by enabling the database server to automatically rotate and delete online message log files, configuring the actions that the server takes to continue processing when memory is critically low, and enabling the server to reserve a specific amount of memory for use when critical rollback activities are needed and the server has limited free memory.
Manage message logs in an embedded environment
You can enable the database server to automatically rotate and delete online message log files, and you can specify the maximum number of online, ON-Bar activity, or ON-Bar debug message log files to rotate. The Scheduler tasks that rotate and delete these message log files are useful for embedded applications, because they reduce DBA or system administrator requirements for managing the logs.
Configuring the frequency of automatic rotation of message log files
You can configure the frequency of the built-in Scheduler tasks that automatically rotate online message log files.

Embedding Informix®
When you embed HCL Informix®, you can use enterprise-class high-availability and high performance with embeddability features such as easy programmability, a small disk and memory footprint, and silent deployment.
- Embedding HCL Informix®
  The Informix® Embeddability Guide describes how to embed HCL Informix in your applications.
  - Overview of embedding Informix® products
    You can embed Informix® products in your applications by taking advantage of customizable deployment options and configurable administration features. You can use the embeddability features in combination with other product features for installation footprint reduction and high-availability clustering to achieve a quicker and easier end-to-end deployment solution.
  - Deploying Informix® software
    The product supports embeddability tools that enable lightweight, faster deployment of the database server and related client programs.
  - Informix® embeddability deployment tutorial
    The purpose of this tutorial is to provide steps and scripts needed for silent end-to-end deployment of HCL Informix® on Linux™ and Windows™ using the deployment assistant and the deployment utility.
  - Manage memory in embedded environments
    You can manage memory in embedded environments by enabling the database server to automatically rotate and delete online message log files, configuring the actions that the server takes to continue processing when memory is critically low, and enabling the server to reserve a specific amount of memory for use when critical rollback activities are needed and the server has limited free memory.
    - Optimize storage
      You can optimize storage by compressing data, configuring the server to add more storage space automatically, and defragmenting partitions. Compressing data reduces the amount of disk space needed for your applications.
    - Manage message logs in an embedded environment
      You can enable the database server to automatically rotate and delete online message log files, and you can specify the maximum number of online, ON-Bar activity, or ON-Bar debug message log files to rotate. The Scheduler tasks that rotate and delete these message log files are useful for embedded applications, because they reduce DBA or system administrator requirements for managing the logs.
      - Enabling and disabling the tasks that automatically rotate message log files
        Before the database server can run the built-in Scheduler tasks that automatically rotate message log files, you must enable each task that rotates a message log file. You only need to enable each task once. You can also disable an enabled task.
      - Tasks that automatically rotate message log files
        A Scheduler task automatically rotates each of the common message log files (online.log, bar_act_log, and bar_debug_log). When the server rotates a log file, the server switches to a new log file and increments the ID numbers for the previous log files by one. When the maximum number of log files is reached, the log file with the highest ID is deleted.
      - Configuring the frequency of automatic rotation of message log files
        You can configure the frequency of the built-in Scheduler tasks that automatically rotate online message log files.
      - Configuring the maximum number of message log files to retain
        You can change the maximum number of online, ON-Bar activity, or ON-Bar debug message log files that the database server retains. This information is stored in the MAX_MSGPATH_VERSIONS, MAX_BAR_ACT_LOG_VERSIONS, and MAX_BAR_DEBUG_LOG_VERSIONS parameters of the ph_threshold table.
      - Reducing the size of message log files
        You can reduce the size of online, ON-Bar activity, or ON-Bar debug message log files by running SQL administration API commands that rotate, truncate, or delete the logs.
    - Reserve memory for critical activities in embedded environments
      You can reserve a specific amount of memory for use when critical activities (such as rollback activities) are needed and the database server has limited free memory. When you reserve memory, critical activities, such as rollback activities, can complete even when you receive out-of-memory errors.
    - Maintain a targeted amount of memory in embedded applications
      You can configure the database server to continue processing when memory is critically low, instead of returning an out of memory error.

Configuring the frequency of automatic rotation of message log files

You can configure the frequency of the built-in Scheduler tasks that automatically rotate online message log files.

About this task

The default frequency of the bar_act_log_rotate, bar_debug_log_rotate, and online_log_rotate tasks is 3 A.M. every 30 days with a maximum of 12 log files, but you can configure the task to run more or less frequently.

Prerequisite:

If you did not enable the task for rotating the message log that you want to configure, do that now.

To configure a task for rotating logs to run more or less frequently:

Procedure

Run the following SQL statements, where days is the number of days between each run:

DATABASE sysadmin;
UPDATE ph_task set tk_frequency = frequency
 WHERE tk_name = task_name;

The task name must be bar_act_log_rotate, bar_debug_log_rotate, or online_log_rotate.

For example, to change the frequency of the online_log_rotate task specify:

DATABASE sysadmin;
UPDATE ph_task SET tk_frequency = INTERVAL (10) 
DAY TO DAY WHERE tk_name = "online_log_rotate";

What to do next

You can also disable the running of message lot rotation tasks, by setting tk_enable to f (false), as follows:

UPDATE ph_task SET tk_enable = f , tk_frequency = tk_frequency
WHERE tk_name = "online_log_rotate";