Please ensure that the memory settings are increased (if possible) for the different UCA services.
This can be done by opening the Deployment Manager and selecting Manage Deployment > Modify Deployment. Click on the machine with the Query Engine and select Edit Properties... . Once in the edit section click on Query Engine Advanced... . Here you can deselect "Calculate Automatically" and enter a RAM value for the Query Engine. Based on how much memory is on the machine, you can try different amounts of RAM until there is positive change.
Afterwards do the same with the Storage Engine Advanced settings.
