A method of monitoring runtime memory usage by a program. The method can include retrieving data from a first region of virtual memory that has been allocated to the program and compressing the data. A data compression rate can be measured. The method further can include generating a notification comprising notification data indicating that the first region of memory was not efficiently used by the program during execution when the data compression exceeds a threshold value or the data compression rate exceeds a statistical value determined from an application's memory usage.