Sizing EC2 for Oracle Fusion Middleware

Hello, not sure what heap file refers to (VMFS? JVM? Other?), so I go for a more generic answer. You could follow two different approaches:

1. Size your instances 1:1 to your on-prem machines (in terms of CPU, RAM and storage) and down-size later, when you have real consumption data. AWS makes changing your EC2 shape very easy and many AWS customers use this approach. You could use our Amazon EC2 instance recommendations in combination with Discovery Connector for this.

2. Try to right-size from the beginning using load metrics from your current system. You might still want to down- or upsize your EC2 instance later, though. For load metrics, you could get the information on average CPU load, used RAM, I/O throughput, IOPS from your monitoring system or from the operating system (e.g. "sar" on Linux). Use this data to see whether your system is under-utilized (e.g., average CPU load being much smaller than provisioned CPU) and a smaller EC2 shape makes sense. See also our documentation chapter Right Size Using Performance Data.