On Fri, Apr 27, 2007 at 10:25:44PM +1000, Nick Piggin wrote: > Linus's favourite jokes about powerpc mmu being crippled forever, aside ;)
Different mmu. The desktop 32bit mmu Linus refered to has almost nothing in common with the mmu on 64bit systems. > >Right this could help but it is not addressing the basic requirement for > >devices that need large contiguuos chunks of memory for I/O. > > Did you read the last paragraph? Or anything Andrew's been writing? > > "After that, I'd find it amusing if HBAs worth thousands of $ have > trouble looking up sglists at the relatively glacial pace that IO > requires, and/or can't spare a few more K for reasonable sglist > sizes, but if that is really the case, then we could use iommus > and/or just attempt to put physically contiguous pages in pagecache, > rather than require it." Real highend HBAs don't have that problem. But for example aacraid which is very common on mid-end servers is a _lot_ faster when it gets continous memory. Some benchmark was 10 or more percent faster on windows due to this. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
