RE: [GIT PULL] mm: frontswap (for 3.2 window)

Dan Magenheimer
2011-10-27T21:49:41Z

> From: Christoph Hellwig [mailto:hch@infradead.org]
> Sent: Thursday, October 27, 2011 3:12 PM
> To: David Rientjes
> Cc: Dan Magenheimer; Linus Torvalds; linux-mm@kvack.org; LKML; Andrew Morton; Konrad Wilk; Jeremy
> Fitzhardinge; Seth Jennings; ngupta@vflare.org; levinsasha928@gmail.com; Chris Mason;
> JBeulich@novell.com; Dave Hansen; Jonathan Corbet; Neo Jia
> Subject: Re: [GIT PULL] mm: frontswap (for 3.2 window)
>
> On Thu, Oct 27, 2011 at 01:18:40PM -0700, David Rientjes wrote:
> > Isn't this something that should go through the -mm tree?
>
> It should have. It should also have ACKs from the core VM developers,
> and at least the few I talked to about it really didn't seem to like it.

Yes, it would have been nice to have it go through the -mm tree.
But, *sigh*, I guess it will be up to Linus again to decide if
"didn't seem to like it" is sufficient to block functionality
that has found use by a number of in-kernel users and by
real shipping products... and continues to grow in usefulness.

If Linux truly subscribes to the "code rules" mantra, no core
VM developer has proposed anything -- even a design, let alone
working code -- that comes close to providing the functionality
and flexibility that frontswap (and cleancache) provides, and
frontswap provides it with a very VERY small impact on existing
kernel code AND has been posted and working for 2+ years.
(And during that 2+ years, excellent feedback has improved the
"kernel-ness" of the code, but NONE of the core frontswap
design/hooks have changed... because frontswap _just works_!)

Perhaps other frontswap users would be so kind as to reply
on this thread with their opinions...

Dan