Brett Glass wrote: > At 04:33 PM 11/26/2009, Manolis Kiagias wrote: > >> Though it seems hyperthreading is improved on the Atom and there is no >> penalty for leaving it on. > > Is there really no penalty? With HZ=1000 there are double the clock > interrupts to be serviced at least. And as I understand it the Atom > has less redundant hardware, so there are less likely to be unused > resources available to the second thread. I am seeing substantially > faster compiles with the SMP option commented out of the kernel. > > --Brett > My tests involved building a custom kernel - I never tried without SMP, just without hyperthreading and there was no appreciable difference. Using -j3 in make kernel, the kernel is built in just about 40 minutes. Without -j same procedure lasts 55 minutes. (I am using an Atom 330 which is dual core)
On a Pentium 4 with HTT, -j actually results in a somewhat slower build. _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
