Re: [PATCH] zram: support a page writeback

From: Minchan Kim
Date: Fri Oct 16 2020 - 16:29:32 EST


Hi Sergey,

On Fri, Oct 16, 2020 at 09:25:47AM +0900, Sergey Senozhatsky wrote:
> On (20/10/12 00:14), Minchan Kim wrote:
> >
> > With the command, zram writeback idle pages from memory to the storage.
> >
> > +If admin want to write a specific page in zram device to backing device,
> > +they could write the page index into the interface.
> > +
> > + echo 1251 > /sys/block/zramX/writeback
> > +
>
> May be we can make it more explicit?
>
> echo "page_index=123" > /sys/block/zramX/writeback
>
> Just in case of future extensions. E.g. someone might want to
> have something like
>
> echo "idle_nr=123" > /sys/block/zramX/writeback
>
> which would write_back 123 idle pages max.
>
> -ss

Make sense. I will use echo "block_index" since page size could be
changed later(e.g., some pages are 4K, some are THP).
I will revise it at next spin.

Thanks, Sergey!