Controls the number of update transactions that are allowed at the same time. When the limits are exceeded, the later arriving update transactions must wait for others to finish.
MAXACTIVEUPDATETRANSACTIONS n
Where n the number of simultaneous active update transactions allowed. The default is 15 or the number of cores on the server machine, whichever is lower.
Each allotted server thread may create child threads for tasks such as parallel calculation, parallel data load or export, and parallel restructuring. If the total number of running threads becomes too high, threads may lose efficiency in contending for server resources. Use this setting to help control the number of simultaneous transactions.
Update transactions, such as calculations and data updates, are more resource-consuming requests than MDX queries or report scripts. When a storage device is fast, Essbase allows more parallel calculation threads to get reasonable throughput; when a storage device is slower, Essbase may need to have a smaller number of parallel calculation or other update threads. You can use MAXACTIVEUPDATETRANSACTIONS to control the number of update transactions.
For example, consider an application that has a CALCPARALLEL setting allowing up to 15 parallel threads. However, the following setting is also in essbase.cfg:
MAXACTIVEUPDATETRANSACTIONS 4
The result is that even there may be 10 scheduled parallel calculation threads, only 4 of them are made active; the rest must wait for one of the active threads to finish.
For similar reasons, you can use parameter MAXTOTALACTIVETRANSACTIONS to control the upper limit of all threads (not just update threads) that can be made active at the same time.
MAXTOTALACTIVETRANSACTIONS should be no larger than the number of server threads, and MAXACTIVEUPDATETRANSACTIONS should be no larger than MAXTOTALACTIVETRANSACTIONS.
MAXACTIVEUPDATETRANSACTIONS 4