I'm running XP in Parallels (1970) on a MBP C2D, and it's running hard on the battery, cutting its life down about 20-30% (estimate). Does Parallels allow the guest OS to take advantage of power saving settings (like Max Battery)? I notice that, after setting XP to Max Battery and then looking in System Information it's reporting that the processor is running at 4.35 GHz, which I assume is a combination of the two processors. So I assume changing to Max Battery doesn't slow the processor down as it would normally. Is it possible to enable this feature somehow, in some release down the road?
Enabling something "down he road" could certainly happen, but for now, guests do not have access to hardware power management.
Well, I don't know how much I would want the guest to mess with the Mac's hardware management...but to enable it to pull less resources or place a lesser demand on the processor would be nice. But I know nothing about CPU architecture or programming, so maybe that's an unrealistic idea.
What you are asking for *is* access to power management. That's how it's done, and that's why it isn't being done now.