Re: [PATCH v2] mm: add ztree - new allocator for use via zpool API

[Vitaly Wool <vitaly.wool@konsulko.com>]

>     Ztree stores integer number of compressed objects per ztree block. These
> blocks consist of several physical pages (from 1 to 8) and are arranged in trees.
>     The range from 0 to PAGE_SIZE is divided into the number of intervals
> corresponding to the number of trees and each tree only operates objects of size
> from its interval. Thus the block trees are isolated from each other, which makes it
> possible to simultaneously perform actions with several objects from different trees.
>     Blocks make it possible to densely arrange objects of various sizes resulting in
> low internal fragmentation. Also this allocator tries to fill incomplete blocks
> instead of adding new ones thus in many cases providing a compression ratio
> substantially higher than z3fold and zbud.
>     Apart from greater flexibility, ztree is significantly superior to other zpool
> backends with regard to the worst execution times, thus allowing for better response
> time and real-time characteristics of the whole system.
> 
> Signed-off-by: Ananda Badmaev <a.badmaev@clicknet.pro>

Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>