6.1-STABLE hangs, ddb shows 'acpi_timer_read'?

[Ivan Voras]

Karl Pielorz wrote:

> Thanks for the link! Anyone know much is all that lot (such as 
> INVARIANTS/WITNESS) etc. likely to slow the machine down? - A few 
> percent? More?

Huge. See http://wikitest.freebsd.org/WitnessPerformance

> 
> I'm just a little hesitant to put it all in, and end up with a machine 
> that's 80% slower :(

Try switching timecounter to TSC, and keep an eye on ntpd to see if your 
time drifts too much.