I applied the 10.6.8 Combo update to a Xserve2,1 and have seen the hwmond
issue. Activity monitor shows that the CPU usage around 93%.
This server hosts our JSS, Netboot services, and is a secondary CasperShare
host. I can't tell that the server is burdened by hwmond. The JSS web
interface and use of Casper Admin responsiveness seems normal.
I haven't applied it yet, but I am considering the workaround provided by
Fred Kinder from the Apple discussion:
https://discussions.apple.com/thread/3138473?start=30&tstart=0
Jason