Minor side-track: when Jay asked for frisbee numbers I noticed that our
times have gotten worse since the USENIX paper. Turns out we were operating at lower BW than the paper (62/Mb sec vs. 70Mb) due to clock granularity. The disk was falling idle too much. Cranked it back up to 72Mb/sec for "standard" (/usr/testbed) images. Actually lowered it to about 54Mb/sec for "user" images that have to be read across NFS (/proj).