Too much disk activity
I have a strange problem.
I am running Ubuntu 8.1 server as a WEB Server(php5, mysql etc) with postfix and proftp. All seems to be running smoothly until the main drive of my raid (2-250 gb IDEs, raid 1-mirror) just goes nuts with reads, I know it is reads since the secondary drive does absolutely nothing while this is happening (I did break the raid and tried it with just the secondary, same thing). The disk activity is so much that it brings the machine to its knees and I can't even reboot the thing without waiting for at least 10 minutes for the prompt. The logs seem to keep writing and I can not see any unusual logging. I have an external USB drive (250 gb) for nightly backups in a cron job but that does not seem to correspond to the problem. The only thing that even comes close to looking like it might be something is quota doing its thing but I do not have any quotas set up so I do not see how that would effect it.
The server is not too busy and as it is a 2.8 gig p4 with 2 gigs of ram running a server without even a desktop installed I would think it would handle it ok.
Any ideas. I hope so since I am going blind reading through all those logs every time it misbehaves (about once a week or so).