I've been working with JIRA and Greenhopper for a few weeks now, and have decided to settle on it as a development aid. That means it's time to stop using the HSQL database.
Loading will be very light; of the 10 users there will only be a maximum of two really active users, interacting intermittently, with state changes on JIRA items at fewer than 100 a day, peak. I have the feeling that supporting this with a SQL Server install would be more than overkill. With SQL Server Express explicitly not supported I have to choose something else.
My question is: Hosted on a machine as described below, which database, among all those openly supported by Atlassian, would work best? Should I run the DB on the hardware, encase it in a VM of its own, or add it to the existing VM?
Hardware: Dual-Core Core 2 processor, 8 GB Memory, mirrored 250 GB hard disk, a third spinning "backup" disk connected internally.
Host OS: Windows Server 2008 R2
VM Host: VMWare Server 2008, currently running one Win Server 2003 R2 instance (2 GB memory allocated in the VM, 20 GB virtual disk, running a lightly loaded IIS instance with a few utility web services)