Oracle Database Discussions

I am trying to figure out how to properly read OEM's Performance graph. During a point of high activity on my database, users complained of having very slow query times and some unresponsiveness from our application. OEM shows high levels of Network, Application, User I/O, CPU and CPU Wait.

My interpretation is:
Network - We have users all over the US and Canada so maybe some of this is to be expected.
CPU and CPU Wait - My server was maxed out so increasing the SGA size could eliminate this problem in the future.

So maybe the assessment above is correct, but if I am wrong I welcome any suggestions.

As for Application and User I/O I am not sure what this is telling me. Any guidance here would be greatly appreciated.

Here is a link to what the OEM graph looks like: https://sites.google.com/site/redroseraces/oem.tif

Thanks, and sorry if this isn't the correct place to post this, but I could not find a more appropriate forum.

mcslain