On Wed, Apr 15, 2015 at 03:34:20PM +0100, Mel Gorman wrote: > On Wed, Apr 15, 2015 at 04:27:31PM +0200, Peter Zijlstra wrote: > > On Wed, Apr 15, 2015 at 09:15:50AM -0400, Waiman Long wrote: > > > I had included your patch with the 4.0 kernel and booted up a 16-socket > > > 12-TB machine. I measured the elapsed time from the elilo prompt to the > > > availability of ssh login. Without the patch, the bootup time was 404s. It > > > was reduced to 298s with the patch. So there was about 100s reduction in > > > bootup time (1/4 of the total). > > > > But you cheat! :-) > > > > How long between power on and the elilo prompt? Do the 100 seconds > > matter on that time scale? > > Calling it cheating is a *bit* harsh as the POST times vary considerably > between manufacturers. While I'm interested in Waiman's answer, I'm told > that those that really care about minimising reboot times will use kexec > to avoid POST. The 100 seconds is 100 seconds, whether that is 25% in > all cases is a different matter. Sure POST times vary, but its consistently stupid long :-) I'm forever thinking my EX machine died because its not coming back from a power cycle, and mine isn't really _that_ large. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>