I'm using the AWS Free Usage Tier, I have one EC2 (t1.micro) instance with Windows Server 2008 and one RDS (t1.micro) instance. After one month of usage now the billing is:
2,000,000 I/O = free tier
1,118,431 I/O = $0.16 exceeded
**3,118,431 I/O TOTAL
10,000,000 I/O = free tier
123,715,372 I/O = $17.32 exceeded
**133,715,372 IO TOTAL
I want to know what one I/O means, I thought that one I/O = one request, but now I think that is not it. Somebody can clarify for me?