On Fri, 26 Jan 2007 11:58:18 -0800 (PST) Christoph Lameter <[EMAIL PROTECTED]> wrote:
> > If the only demonstrable benefit is a saving of a few k of text on a small > > number of machines then things are looking very grim, IMO. > > The main benefit is a significant simplification of the VM, leading to > robust and reliable operations and a reduction of the maintenance > headaches coming with the additional zones. > > If we would introduce the ability of allocating from a range of > physical addresses then the need for DMA zones would go away allowing > flexibility for device driver DMA allocations and at the same time we get > rid of special casing in the VM. None of this is valid. The great majority of machines out there will continue to have the same number of zones. Nothing changes. What will happen is that a small number of machines will have different runtime behaviour. So they don't benefit from the majority's testing and they don't contrinute to it and they potentially have unique-to-them problems which we need to worry about. That's all a real cost, so we need to see *good* benefits to outweigh that cost. Thus far I don't think we've seen that. - 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/
