[EMAIL PROTECTED] wrote: > > On Wed, 20 Mar 2002, Gordon Pearce wrote: > > > > > > > > > Why will it be faster? Is it something to do with the way the array is > > > > referenced? > > > > > > > From the previous two email, yep, that's pretty much what I thought. > > I never thought about the cache thing though. I wonder if it makes a > > difference with no cache? > > I think an experiment is in order... > > Well, you could also get a difference from another effect, if your > arrays are large. Think virtual memory. If your arrays take a number > of pages larger than the number of slots in the TLB (the TLB is a fast > cache for page table lookups, ie virtual->physical address lookups), > then wandering back and forth through memory will cause extra memory > accesses to re-fetch the entries that are pushed out of the TLB. >
Atlas Blas optimises itself on crazy stuff like this. http://www.netlib.org/atlas/ Quite frankly, it scares me :). Thanks, Allan -- Claiming that your operating system is the best in the world because more people use it is like saying McDonalds makes the best food in the world. -------------------------------------------------------------------- http://www.lug.org.uk http://www.linuxportal.co.uk http://www.linuxjob.co.uk http://www.linuxshop.co.uk --------------------------------------------------------------------
