We are about to implement a seperate Web and Database server, moving from our current 'all in one' server.

Each server will be a Dual P3 2.6Ghz machine, with RAID 1 using SCSI 10K disks.

We will be using Mysql 4.1 on one server, and Apache 2 and PHP on the other

Every week we send out a personalised (so a bit of database crunching required) email to our 18,000 members. This takes about an hour to run, and during this time the site slows down considerably.

Now assuming that QMail is Disk IO bottlenecked, rather than CPU- is this correct, what server would it be better running on - the web server or the DB server?

Thanks for your help