Does anyone have any numbers or good resources on the disk IO performance penalty for a non-enlightened guest(Windows XP) vs enlightened guest (Windows 7) running in a hypervisor?
Hyper-V in particular, but VMWare ESX numbers would also be useful.
I haven't done serious experimenting yet, but in the case of XP I noticed very poor disk performance initially. There may also be some obvious tips for configuring for good disk performance. I started at dynamic disk (bad), moved to fixed disk (still bad), then moved to direct disk access (better, but not great).
This is a basic test so far - a single VM. I'm still experimenting and early planning. My goal is consolidation, even if each VM still needs its own disk (build server load which is CPU and IO intensive). Windows 7 is an option but I will also need at least a couple running XP.