John-Mark Gurney wrote: > > Dag-Erling Smorgrav scribbled this message on Aug 4: > > "Kelly Yancey" <kby...@alcnet.com> writes: > > > [...] > > > > Which reminds me - has anyone thought of using DMA for zeroing pages, > > to avoid cache invalidation? The idea is to keep a chunk of zeroes on > > disk and DMA it into memory instead of clearing pages "manually". This > > assumes your disk supports DMA, of course. > > has anyone looked at using two dma channels tied together to do memory > copies? I haven't studied the DMA specs, but from what I know of the > dma on x86 machines is that you could tie two dma channels together one > to feed the other, and this would allow you to copy memory w/o using the > processor... > > w/ dma channels, we can just make a copy of the base zero page...
Im not sure how much relevance this has, but many years ago I was writing video routines, I thought using software initiated DMA to copy pages of memory from one place to another would be a really cool and quick solution.
