Too slow to retreive records from AWS redshift or RDS onto AWS Jaspersoft

We are using the Jaspsersoft software through AWS and are facing performance issue with the AdHoc view reports. 

 

In the adhoc view, each time a row/column is added/removed , it hits the database and gets the result set to display it. We have data over 5 million records, which creates lot of latency in displaying the data for each change in report parameters.

 

The latency is significant after adding three or more fields in the rows  and three or more measures in the crosstab.

 

 

So, we are trying to see if jaspersoft have in-memory option that can be configured at AWS or can you help us in providing an alternate solution to our problem