Re: The performance and behaviour of the anti-fragmentation related patches

Christoph Lameter
2007-03-02T04:33:10Z

On Thu, 1 Mar 2007, Andrew Morton wrote:

> Sorry, but this is crap. zones and nodes are distinct, physical concepts
> and you're kidding yourself if you think you can somehow fudge things to make
> one of them just go away.
>
> Think: ZONE_DMA32 on an Opteron machine. I don't think there is a sane way
> in which we can fudge away the distinction between
> bus-addresses-which-have-the-32-upper-bits-zero and
> memory-which-is-local-to-each-socket.

Of course you can. Add a virtual DMA and DMA32 zone/node and extract the
relevant memory from the base zone/node.