Re: [PATCH 0/8] zcache: page cache compression support

Christoph Hellwig
2011-01-20T12:48:09Z

On Thu, Jan 20, 2011 at 07:33:29AM -0500, Nitin Gupta wrote:
> I just started looking into kztmem (weird name!) but on
> the high level it seems so much similar to zcache with some
> dynamic resizing added (callback for shrinker interface).
>
> Now, I'll try rebuilding zcache according to new cleancache
> API as provided by these set of patches. This will help refresh
> whatever issues I was having back then with pagecache
> compression and maybe pick useful bits/directions from
> new kztmem work.

Yes, we shouldn't have two drivers doing almost the same in the
tree. Also adding core hooks for staging drivers really is against
the idea of staging of having a separate crap tree. So it would be
good to get zcache into a state where we can merge it into the
proper tree first. And then we can discuss if adding an abstraction
layer between it and the core VM really makes sense, and if it does
how. But I'm pretty sure there's now need for multiple layers of
abstraction for something that's relatively core VM functionality.

E.g. the abstraction should involve because of it's users, not the
compressed caching code should involve because it's needed to present
a user for otherwise useless code.