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.
There are a lot of factors that will impact your IO requests, as @datasage says, try it and see how it behaves under your scenario. Micro Linux instances are incredible cheap to begin with, but if you are really concerned, setup a billing alert that will notify you when your usage passes a pre-determined threshold - if it suddenly spikes up, you can take some action to shut it down if that is what you want.
https://portal.aws.amazon.com/gp/aws/developer/account?ie=UTF8&action=billing-alerts
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 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.
