On Mon, 2002-10-14 at 20:35, Robert L. Cochran wrote: > I'm new to the CPU-level stuff and don't have much background in them. > So some of the terms are new for me. Let me get really basic: why would > you want multiple processors on a motherboard as opposed to a single > fast processor? I take it that the Xeon line is for multiple CPU > motherboards -- you don't just run one Xeon, am I right? What does it > mean, to be 'cpu cache bound'? Sure you can run one P-IV Xeon, I have several systems here that do just that. I tend to leave the HyperThreading turned on "because its cool" to "see" 4 cpu's in my desktop. Although I know some things I do cause it to actually run slower. Being cache-bound, IIRC is that the data the processors want can't fit in the cache, so it must go to main memory (slower) for the data, or worse all the way out to the disk (slowest) to get it. On a P-IV Xeon, if you are going out to the disk to fill the cache, you are hanging up what appears to be two cpu's as they share cache. However, if you are running normally IO bound processes, where one cpu is just waiting on disk access for something before continuing with it's task, the other "half" of the cpu can already be doing something else, effectively speeding things up. > Do your comments also mean the Red Hat kernel won't need testing on the > new Hyper Threaded P4s? Sure it will, but the technology is maturing in the Xeons, and will (unless Intel throws a curveball) probably work just fine as is. Remember that you will probably NOT be able to drop a HyperThreading aware P-IV into your current P-IV motherboard and use HyperThreading unless the chipset and bios support it as well. Normal P-IV's aren't slow enough to consider junking just to get your hands on a HyperThreading version. -- ********************************************************************** Chris Kloiber, RHCE Red Hat,Inc. Hardware Certification aka 1801 Varsity Dr. Enterprise Support "WireHead" Raleigh, NC 27606 ********************************************************************** -- Psyche-list mailing list Psyche-list@redhat.com https://listman.redhat.com/mailman/listinfo/psyche-list
