[Lguest] [PATCH RFC/RFB] x86_64, i386: interrupt dispatch changes

[H. Peter Anvin]

Okay, after spending most of the day trying to get something that isn't
completely like white noise (interesting problem, otherwise I'd have
given up long ago) I did, eventually, come up with something that looks
like it's significant.  I did a set of multiple runs, and am looking for
the "waterfall points" in the cumulative statistics.

http://www.zytor.com/~hpa/baseline-hpa-3000-3600.pdf

This particular set of data points was gathered on a 64-bit kernel, so I
didn't try the segment technique.

It looks to me that the collection of red lines is enough to the left of
the black ones that one can assume there is a significant effect,
probably by about a cache miss worth of time.

	-hpa