You can use the DMU population change option to reallocate the number of areas for a given database structure, specify automatic population increase of a structure, or request a warning when the population approaches the limit. This facility should be used when:
DMS II limit errors occur for your built application.
You want to reallocate disk space to database structures without having to rebuild your application.
You want to allow an automatic increase in the population of your built System.
You want to be warned when the population of your built application is approaching its limit.
The DMU population change process updates the database control file database/ CONTROL, and creates a temporary DASDL file called POPULATION/DMS.
You can increase or decrease populations. If you decrease a structure's population, a warning message is displayed. Transmit the same value again to confirm. If you enter less than the current population, a DMS II limit error occurs the next time DMS II tries to add more disk area for that structure.
You can automatically increase the population of a structure, or request a warning when the population approaches the limit.
When you select the population change option on the DMU Home screen, a screen is displayed listing structures for you to select for population change. Enter any non-blank character to indicate that you wish to make a population change for that structure.
The automatic Population Increase % property can be set to any value from 0 through 100. A setting of 0 means that the population is not automatically increased. Any other value allows the population to be increased automatically by up to that percentage if the population exceeds its current limit. This happens without interruption unless the structure has reached the system maximum of 1000 areas.
The Population Warning % property can be set to any value from 0 through 99. The application issues a warning message when the population reaches that percentage of the limit. To suppress the message, enter N in the Warning Display property.
Each dataset that you select is then displayed separately on another screen. The screen shows the following values:
The current population setting
The actual population
The number of areas
The population increase percentage
The population warning percentage
The warning display setting
You can enter new values for the population setting, population increase percentage, population warning percentage and warning display setting.
Following the dataset, each Profile (set or subset) name is listed, with its current population and a property for you to enter the new population values required. After making your selections, transmit. If there are more datasets, another screen is returned.
If you decrease the population for a structure, a warning message is displayed. Transmit the same value again to confirm. If you enter a value less than the current actual population, a DMS II limit error occurs the next time DMS II tries to add more disk area for that structure.
When all datasets have been displayed, DMU automatically initiates DASDL compilation as required, and then returns you to the DMU Home screen.
Note: Your Specification should also be updated to reflect the new EXPECTED.NO or MONTHLY.VOL values and then rebuilt, otherwise any population changes you have made using DMU are lost when your application is next built.