You can tune your resource requests by specifying a high-water mark and low-water mark in the application profile.
Both high-water mark and low-water mark are expressed as the ratio of the number of unprocessed tasks to the number of CPU slots. Unprocessed tasks include both running and pending tasks.
Together, the high-water mark and low-water mark define a range of satisfactory slot allocation, in which the application does not need to request additional resources or release excess resources.
High-water mark allows user to define the threshold for the application as a whole, to request more resources in order to meet its service level requirement. It defines the maximum ratio of unprocessed tasks of open sessions to CPU slots before more resources are requested to meet the service level requirement of the application.
For example, a high-water mark of 5 means that you want at least one CPU slot for every 5 unprocessed tasks in open sessions.
Low-water mark allows you to define the threshold for the application as a whole, to return resources that are no longer needed. These returned resources can then be used by other applications.
The low-water mark is the minimum ratio of unprocessed tasks of open sessions to CPU slots before resources are released and made available for other applications to use.
The low-water mark should be configured to be less than or equal to the high-water mark.
For example, a low-water mark of 2 and a high-water mark of 5 means it is satisfactory to have between 2 and 5 tasks for each CPU slot. When there is heavy workload, there can be 5 tasks per CPU slot. When there is light workload, you want to return excess CPU slots until there are at least 2 tasks per CPU slot.