How to control linux system on amazon ec2 without cloudwatch?

Question

I would like to track the following Amazon ec2 instances loaded by amazon linux every X minutes:

disk
statistics process statistics (similar to what it does top)
Using ram check if my scripts are working fine

Should I use my own scripts and things, or are there any tools that already achieve this?
I searched and had a suggestion about munin

What is apparently the best approach?

Answer 1

Here is a great article about scale. About halfway through, the author lists the monitoring tools and how they differ.

http://highscalability.com/blog/2010/8/16/scaling-an-aws-infrastructure-tools-and-patterns.html

Cacti, , / ( , ). Munin - , , .