SP_THRESHOLD configuration parameter
Use the SP_THRESHOLD configuration parameter to define the minimum amount of free kilobytes that can exist in a storage space before HCL OneDB™ automatically runs a task to expand the space, either by extending an existing chunk in the space or by adding a new chunk.
- onconfig.std value
- SP_THRESHOLD 0
- values
0
= No threshold. The trigger that runs the storage space monitoring (mon_low_storage) task for adding space when space is below the threshold is disabled.1 - 50
= A threshold that is a percentage of free kilobytes in a storage space.If the value is 50 or below, HCL OneDB interprets the value as a percentage (for example, 10 = 10 percent and 2.84 = 2.84 percent).
1000
to the maximum size of a chunk = A threshold that is either 1000 kilobytes or the maximum size of the chunk on the current platform.If the value is 1000 or higher, HCL OneDB interprets the value as a specific number of kilobytes.
Values 50 - 1000 are not valid.
- takes effect
- After you edit your onconfig file and restart the database server.
Usage
When you set the SP_THRESHOLD configuration parameter to a valid value that is greater than 0, the built-in Scheduler task, mon_low_storage, runs automatically when the free space in a dbspace, temporary dbspace, sbspace, temporary sbspace, or blobspace falls below the threshold.
Suppose the value of the SP_THRESHOLD configuration parameter value is 5.5, which the server interprets as 5.5 percent. If a space runs low on free pages, and the free space percentage falls below 5.5 percent and remains below that level until the mon_low_storage task runs next, that task will attempt to expand the space. If the SP_THRESHOLD configuration parameter is set to 50000 and a space has fewer than 50000 free kilobytes, that space will be expanded the next time mon_low_storage task runs.
A value of 0 turns off the mon_low_storage task, and prevents the server from extending any space. However, a value of 0 does not affect the ability of the server to extend a space when all free pages are depleted and more are needed.
The value specified in the SP_THRESHOLD configuration parameter applies to all spaces belonging to the server.