FC4 and xen0 performance

[Jeffrey Buell]

I installed FC4 test1 and xen0 straight from Fedora and ran some simple
kernel microbenchmarks (loops over getpid, fork/wait, signal, etc.) and the
results are pretty ugly compared to a 2.6.1 install. FC4 ranges from 1.5X to
20X slower, while xen0 is about 2X to 6X slower.  Is this expected? I'm
looking for configuration differences now, but I'm wondering if anybody can
comment on how FC4 and xen0 were built. debug? asserts? One difference
between FC4 and xen0 is that FC4 was configured with HIGHMEM and xen0 wasn't.

Thanks,

Jeff