Question: I am hosting my application on amazon ec2 , on one of their micro linux instances. 

It costs (apart from other costs) $0.11 per 1 million I/O requests . I was wondering how much I/O requests does it take when I have say 1000 users using it for say 1 hours per day for 1 month ?

I guess my main concern is : if a hacker keeps hitting my login page (simple html) , will it increase the I/O request count ? I guess yes, as every time the server needs to do something to server that page.

Answer: 
Take a look at CloudWatch, and (for free) set up a VolumeWriteOps and VolumeReadOps alarm to work with Amazon Simple Notification Service (SNS) to send you a text message and eMail notice right away if things get too busy, *before* the bill gets high! (A billing alert will let you know too late - after it has reached the threshold.)

In general though, from my experience, you will not have the problem you outline. Scan the EC2 Discussion Forum at [forums.aws.amazon.com](https://forums.aws.amazon.com/forum.jspa?forumID=30) where you would find evidence of this kind of problem if were prevalent; it does not seem to be happening.
@Dilpa yes you are right. If some brute force attack will occur to your website eg: somebody hitting to your loginn page then it will increase the server I/O if you enable loging for your webserver. Webserver will keep log to it's log files of every event and that will increase your I/O. Just verify your webserver log for such kind of attack and you can prevent them.