SUMMARY
Single instance synthetic compression properties
ISSUE
Purpose
Turn off compression for synthesis.
Description
For performance reasons it is sometimes desirable to sacrifice retention for speed. With this in mind it is possible to turn off the generation of synthetics that are compressed. This will produce a large synthetic master, but it will be generated very quickly.
Cause
Sometimes a synthetic master can take many hours to generate, which can bog down a system, or get in the way of replication. In such an instance a user may want to generate a synthetic master faster, and is willing to sacrifice retention for the faster master. This property can be used to turn off compression on an instance by instance basis (client).
Resolution
This tool should only be used by tech support when tunneled onto a customer DPU.
An application is included in the /usr/bp/bin directory called app-properties. When run it produces a small menu with four options, like the menu below:
[1] Set a keyword/value property for an application instance.
[2] Get a keyword/value property for an application instance.
[3] Delete the application instance keyword entry. The keyword must exist, and the instance id will be checked and confirmed that it is a valid entry in the application instances table.
[4] Quit.
Enter the number of your menu choice:
Option 1 allows the user to set a property on an instance. In this case the property we want to set is compress-synth-backup (excluding quotes). This has a value of “no” or “yes”, case does not matter but spelling is critical. When option 1 is selected you as asked for the instance ID that this property applies to. Enter the instance ID number and press return. You are now asked for the Keyword (name of property), which is compress-synth-backup, and press enter. The next prompt asks for the value to associate with this property. In the case of compression it is either “yes” (compress the synthesized full) or “no” (not compress the synthesized full). Press enter and the property and value for the instance ID is displayed. You are done adding the property.
Option 2 is used to query the property value. It first asks for the Instance ID, enter this value and press return. It then asks for the property, in this case is would be compress-synth-backup and press return. The result is the property setting for this property and instance ID.
Option 3 is used to remove a property value.
Option 4 is to quit the application.
For the property compress-synth-backup the default behavior is to always compress the synthetic backup. The valid values are, without quotes, yes or no. Anything else will default to yes.
Third-Party Sources
None.