high load with 5.1-release?

[Liam Slusser]

One of my freebsd boxes has a huge load but it doenst show any cpu usage, it
always shows ~70% idle.

Its a dual cpu intel xeon 2.4ghz with hyberthreading (freebsd shows 4cpus)

uname -a
FreeBSD gflux.tiora.net 5.1-RELEASE FreeBSD 5.1-RELEASE #2: Thu Sep 18
16:20:28 PDT 2003     root at gflux.tiora.net:/usr/src/sys/i386/compile/gflux
i386

last pid:  2456;  load averages:  9.66, 12.08, 14.41                    up
17+16:43:08  15:04:30
217 processes: 11 running, 205 sleeping, 1 zombie
CPU states:  9.5% user,  4.3% nice, 15.1% system,  0.8% interrupt, 70.3%
idle
Mem: 333M Active, 289M Inact, 224M Wired, 46M Cache, 111M Buf, 93M Free
Swap: 512M Total, 59M Used, 453M Free, 11% Inuse

Im aware the server is highly busy, and its always very fast.  I just dont
understand why it always says there is always 70% idle cpu time?  iostat
says the same thing.

I can do a make -j 12 world, and it still shows 70% idle cpu time.

Any thoughts?

thanks,
liam