<quote who="Juli Mallett"> > * De: Odhiambo Washington <[EMAIL PROTECTED]> [ Data: > 2003-01-28 ] > [ Subjecte: Re: Force 1 CPU on SMP kernel? ] >> * Ceri Davies <[EMAIL PROTECTED]> [20030128 12:50]: >> wrote: >> > On Mon, Jan 27, 2003 at 11:33:02PM -0500, Adam Migus >> wrote: >> > > Hi, >> > > I'm doing some performance analysis on FreeBSD. I would >> like to be able to make an SMP kernel use only one CPU. >> Of course I realize running GENERIC would only use 1 CPU >> but the concern is that the overhead assoicated with SMP >> will skew the statistics. So my question is what would >> be the 'best' way to make an SMP kernel only start/use >> CPU0? >> > >> > Yank the others ? >> > >> >> What about building two kernels, one SMP, the other non-SMP, >> then just boot wheichever kernel you want? Doesn't it server >> same purpose? Better than Ceri's idea ;) > > You're missing the point. He wants to boot only the bootstrap > processor, none of the APs, but still be running an SMP > kernel. I think checking how much overhead "SMP" and > "APIC_IO" add is a noble goal, and throwing real SMP into the > mix would be dumb.
Yes, just to be more explicit. What I want to do is get the 'real' difference a second processor makes. ie. If I run GENERIC I'm not incurring the overhead associated with SMP/APIC. I want to use the same kernel making as small a change as nessessary to have the machine start/use just one CPU. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
