On (22/11/22 12:00), Sergey Senozhatsky wrote: > On (22/11/21 15:44), Johannes Weiner wrote: > > This looks pretty great. > > > > However, I'm curious why it's specific to zram, and not part of > > zsmalloc? That way zswap would benefit as well, without having to > > duplicate the implementation. This happened for example with > > page_same_filled() and zswap_is_page_same_filled(). > > > > It's zsmalloc's job to store content efficiently, so couldn't this > > feature (just like the page_same_filled one) be an optimization that > > zsmalloc does transparently for all its users? > > Yea, that's a much needed functionality, but things may be "complicated". > We had that KSM-ish thing in the past in zram. Very briefly as we quickly > found out that the idea was patented by some company in China and we couldn't > figure our if it was safe to land that code upstream. So we ended up dropping > the patches. > > https://lore.kernel.org/lkml/1494556204-25796-1-git-send-email-iamjoonsoo.kim@xxxxxxx/ IIRC that was patent in question: https://patentimages.storage.googleapis.com/e2/66/9e/0ddbfae5c182ac/US9977598.pdf
