Hi Dave, Dave Walker wrote:
> Modern machines have hyperthreaded CPU cores, so you are more likely > to load multiple applications and still get decent performance if > you have lots of memory available. A good theory, in practice it is let down by either the design of the Core Duo chip or the OS not utilising things properly - I'm not sure which. In a Core Duo, all accesses to the Input Output sub-systems *must* be done by the first core and only by the first core. I read this about a month ago in one of the mainstream computer comics - can't remember which one now that I need to. Apparently, core 1 says to core 0, stop that and service this I/O request for me, so core 0 has to comply, so anything running on the first core is interrupted while it passes on I/O requests for the second core, and the second core is delayed in processing I/O while it hangs around waiting for the first core to pay attention! An interesting design I thought when I read it. Cheers, Norman. _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm