Amazon EC2 EBS IO Count is high

I am running Ubuntu 11.04 +Apache +Mysql +php on free micro tier of Amazon EC2, complete root is attached to EBS.. The db size of mysql is 700 MB.. but in just 45 hours of running the instance.. I/O count is 713,136... ?? I have installed phpbb on my website and it is getting around开发者_运维问答 4000 pageview/day. how can I optimize the I/O..

You can use APC (Alternate PHP Caching) so that there is no I/O request for cached pages. If anybody else has better idea please post it.