If you don’t care about Xcode then there are quite a few free and paid tools to do the job, try searching in AppStore.
- Mac Rumours (macrumours.com)
- Using Activity Monitor to read System Memory (apple.com)
- Mac OS X Internals – A Systems Approach by Amit Singh (amazon.com)
- Can I force my Mac to make better use of inactive memory (apple.stackexchange.com)
- Trouble understanding Inactive Memory in Mac OS X (stackoverflow.com)