Re: what's cooking in zram for 4.1

Karel Zak
2015-05-11T11:38:43Z

On Sat, May 09, 2015 at 01:21:48PM +0900, Sergey Senozhatsky wrote:
> There will be some user-space visible changes in zram 4.1 we'd love to let you know
> about.

Thanks.

> 2) zram has deprecated some of the existing stat sysfs attributes. we will
> consolidate zramX device's stats in 3 files, rather than having N files (per-stat).

sysfs attributes used by zramctl(8) are:

disksize
orig_data_size
compr_data_size
comp_algorithm
max_comp_streams
mem_used_total
reset

> -- /sys/block/zram<id>/mm_stat
>
> The stat file represents device's mm statistics. It consists of a single
> line of text and contains the following stats separated by whitespace:

hmm... frankly, the reason why I love /sys and why hate /proc is
value-per-file. You do not need special parsers to read from /sys
(usually).

> orig_data_size
> compr_data_size
> mem_used_total
> mem_limit
> mem_used_max
> zero_pages
> num_migrated

Why do you need all in one file? ... to provide consistent statistics?

Karel

--
Karel Zak <kzak@redhat.com>