I remember that my benchmarks took a 7% hit after installing
SP2. They added a bunch of security stuff and I'd guess that there are some security processes running around that take up some extra memory now.
One other thing is that Whidbey has buffer overflow checking in
it turned on by default. At the beginning of a routine, a
cookie is created and at the end of the routine, the cookie is
checked. These are done with system service (I think) calls.
Consider that every application routine goes through this
checking and you see the source of some performance loss. I
turn the switch off (if your application checks calls correctly,
it shouldn't have buffer overflow problems) to get performance
levels back.
I take it that noone here really knows, from a software
engineering perspective, why Vista is so resource hungry.
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