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

From: Minchan Kim
Date: Sun Dec 02 2018 - 21:41:54 EST


On Mon, Dec 03, 2018 at 11:30:40AM +0900, Sergey Senozhatsky wrote:
> On (12/03/18 08:18), Minchan Kim wrote:
> >
> > Per andrew's comment:
> > https://lkml.org/lkml/2018/11/27/156
> >
> > I need to fix it to represent 4K always.
>
> Aha.
>
> Then we need to increase bd_writes PAGE_SIZE/4K times in writeback_store()?
>
> wb_count = atomic64_inc_return(&zram->stats.bd_writes);
> ...
> if (wb_limit != 0 && wb_count >= wb_limit)
> zram->stop_writeback = true;
>
> bd_wb_limit is in 4K units; but in writeback_store() we alloc a full page
> and write it to the backing device. So the actual number of written bytes
> can be larger on systems with page_size > 4K. Right?

Hey Sergey,

I changed interface in recent version v4. I belive it would be more
straigtforward for user. Could you review it?

Thanks!