On Mon, Jan 09, 2023 at 12:38:35PM +0900, Sergey Senozhatsky wrote: > Computers are bad at division. We currently decide the best > zspage chain size (max number of physical pages per-zspage) > by looking at a `used percentage` value. This is not enough > as we lose precision during usage percentage calculations > For example, let's look at size class 208: > > pages per zspage wasted bytes used% > 1 144 96 > 2 80 99 > 3 16 99 > 4 160 99 > > Current algorithm will select 2 page per zspage configuration, > as it's the first one to reach 99%. However, 3 pages per zspage > waste less memory. > > Change algorithm and select zspage configuration that has > lowest wasted value. > > Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Acked-by: Minchan Kim <minchan@xxxxxxxxxx>
