ASO performance optimization needed

Currency conversion process on ASO taking excessively longer time and when we verify the logs, we can see - The formula for member is complex. If possible, add a non-empty directive to optmize for sparse data
Can some one advise if there are any performance tuning steps that we can implement? FYI - We have tried compact outline and Essbase cache size increase but there is no much benefit

Thanks, 
Kiran