On Fri, Jul 13, 2001 at 09:32:54AM -0500, Dave Sherohman wrote: | On Fri, Jul 13, 2001 at 12:13:20PM +0100, J.A.Serralheiro wrote: | > On Fri, 13 Jul 2001, Alexey wrote: | > > You know, while running DOS or Windows, the CPU is hot (I can touch it), | > > even if I do nothing. It becomes cool under Linux!!! | > | > strange, never heard of that. | | Linux (and NT, incidentally) sends HLT (HaLT) instructions to the CPU | telling it to shut itself down (until the next interrupt) when there's | nothing for it to do. So if your linux system tells you you're at | 30% CPU utilization, the CPU is essentially turned off 70% of the | time.
This would also (theoretically) lead to less power consumption and a lower electric bill. Pretty nice! Say, does that HLT instruction work on a i486 or only on newer CPUs? I also seem to recall, back when I was learning m68k assembly, that the halt instruction on there shouldn't be used if you want to ever do any procesing again (without a reboot). -D
