On Mon, Oct 31, 2022 at 02:41:07PM +0900, Sergey Senozhatsky wrote: > Provide a simple documentation for pages_per_pool_page ZRAM > device attribute. > > Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> > --- > Documentation/admin-guide/blockdev/zram.rst | 38 ++++++++++++++++----- > 1 file changed, 30 insertions(+), 8 deletions(-) > > diff --git a/Documentation/admin-guide/blockdev/zram.rst b/Documentation/admin-guide/blockdev/zram.rst > index 010fb05a5999..4cb287520d45 100644 > --- a/Documentation/admin-guide/blockdev/zram.rst > +++ b/Documentation/admin-guide/blockdev/zram.rst > @@ -112,7 +112,29 @@ to list all of them using, for instance, /proc/crypto or any other > method. This, however, has an advantage of permitting the usage of > custom crypto compression modules (implementing S/W or H/W compression). > > -4) Set Disksize > +4) Set pages per-pool page limit: Optional > +========================================== > + > +zsmalloc pages can consist of up to ZS_DEFAULT_PAGES_PER_ZSPAGE (single) > +physical pages. The exact number is calculated for each zsmalloc size > +class during zsmalloc pool creation. ZRAM provides pages_per_pool_page > +device attribute that lets one adjust that limit (maximum possible value > +is ZS_MAX_PAGES_PER_ZSPAGE). The default limit is considered to be good > +enough, so tweak this value only when the changes in zsmalloc size classes > +characteristics are beneficial for your data patterns. The limit on the > +pages per zspages (currently) should be in [1,16] range; default value > +is 4. I think we need to introudce pros and cons for user to decide it since it's not familiar with admin. I think It would need more explanation about zsmalloc internal(especailly zspage and size classes)
