Re: [PATCH v3 7/7] zram: writeback throttle

From: Minchan Kim
Date: Sun Dec 02 2018 - 18:18:37 EST


On Thu, Nov 29, 2018 at 11:23:58AM +0900, Sergey Senozhatsky wrote:
> On (11/27/18 14:54), Minchan Kim wrote:
> > diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram
> > index 65fc33b2f53b..9d2339a485c8 100644
> > --- a/Documentation/ABI/testing/sysfs-block-zram
> > +++ b/Documentation/ABI/testing/sysfs-block-zram
> > @@ -121,3 +121,12 @@ Contact: Minchan Kim <minchan@xxxxxxxxxx>
> > The bd_stat file is read-only and represents backing device's
> > statistics (bd_count, bd_reads, bd_writes) in a format
> > similar to block layer statistics file format.
> > +
> > +What: /sys/block/zram<id>/writeback_limit
> > +Date: November 2018
> > +Contact: Minchan Kim <minchan@xxxxxxxxxx>
> > +Description:
> > + The writeback_limit file is read-write and specifies the maximum
> > + amount of writeback ZRAM can do. The limit could be changed
> > + in run time and "0" means disable the limit.
> > + No limit is the initial state.
> > diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt
> > index 906df97527a7..64b61925e475 100644
> > --- a/Documentation/blockdev/zram.txt
> > +++ b/Documentation/blockdev/zram.txt
> > @@ -164,6 +164,8 @@ reset WO trigger device reset
> > mem_used_max WO reset the `mem_used_max' counter (see later)
> > mem_limit WO specifies the maximum amount of memory ZRAM can use
> > to store the compressed data
> > +writeback_limit WO specifies the maximum amount of write IO zram can
> > + write out to backing device as 4KB unit
> ^^^^
> page size units?

Per andrew's comment:
https://lkml.org/lkml/2018/11/27/156

I need to fix it to represent 4K always.