In a message dated 9/17/02 7:55:28 PM, [EMAIL PROTECTED] writes:
<< Because of the multiprocessing ability of X, my hunch is that a MP card, even with dual 180 604s, should run acceptably-at least as well as a G3 300. This guess is because X can split finder functions and programs between the 2 processors. Note that dual processors are more effecient when you are running multiple apps that are not designed for them or when running one MP enabled app. >> There is only one cache on an Apple MP-equipped machine, and considerable logic is included to make certain that one processor doesn't step on the other. Therefore, you really can't get 2X out of two processors as any cache writes must, necessarily, be single-threaded. Most optimistic case is about 1.8X, and most aps can't achieve that. Mainframes overcome this problem long ago, and at my former employer we successfully made 16-way processors, in which the individual processors didn't get throttled down when accessing cache. Of course, the operating system had considerable code which facilitated multiprocessing, and it has had since at least 1972. Yeah ... multiprocessing is at least 30 years young. Peter. -- PCI-PowerMacs is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | -- Sonnet & PowerLogix Upgrades - start at $169 | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> PCI-PowerMacs list info: <http://lowendmac.com/lists/pci-powermacs.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive:<http://www.mail-archive.com/pci-powermacs%40mail.maclaunch.com/> Using a Mac? Free email & more at Applelinks! http://www.applelinks.com
