Re: DISCONTIGMEM is deprecated

From: Christoph Hellwig
Date: Sun Apr 28 2019 - 04:11:23 EST


On Wed, Apr 24, 2019 at 02:33:53PM +0300, Mike Rapoport wrote:
> On Tue, Apr 23, 2019 at 12:13:54AM -0700, Christoph Hellwig wrote:
> > On Sun, Apr 21, 2019 at 10:16:04PM +0100, Mel Gorman wrote:
> > > 32-bit NUMA systems should be non-existent in practice. The last NUMA
> > > system I'm aware of that was both NUMA and 32-bit only died somewhere
> > > between 2004 and 2007. If someone is running a 64-bit capable system in
> > > 32-bit mode with NUMA, they really are just punishing themselves for fun.
> >
> > Can we mark it as BROKEN to see if someone shouts and then remove it
> > a year or two down the road? Or just kill it off now..
>
> How about making SPARSEMEM default for x86-32?

Sounds good.

Another question: I always found the option to even select the memory
models like a bad tradeoff. Can we really expect a user to make a sane
choice? I'd rather stick to a relativelty optimal choice based on arch
and maybe a few other parameters (NUMA or not for example) and stick to
it, reducing the testing matrix.