On Wed, Dec 11, 2013 at 11:09:59AM +0900, Minchan Kim wrote: > Hello Greg, > > On Wed, Dec 11, 2013 at 11:04:35AM +0900, Minchan Kim wrote: > > Zram is a simple pseudo block device which can keep data on > > in-memory with compressed[1]. > > > > It have been used for many embedded system for several years > > One of significant usecase is in-memory swap device. > > Because NAND which is very popular on most embedded device > > is weak for frequent write without good wear-level > > and slow I/O hurts system's responsiblity so zram is really > > good choice to use memory efficiently. > > > > In previous trial, there was some argument[2] that zram has > > similar goal with zswap so let's merge zram's functionality > > into zswap via adding pseudo block device in zswap but I and > > some people(At least, Hugh and Rik) believe it's not a good idea. > > [2][3][4] and zswap might go writethrough model[5]. It makes > > clear difference zram and zswap. > > > > Zram itself is simple/well-designed/good abstraciton so it has > > clear market(ex, Android, TV, ChromeOS, some Linux distro) which > > is never niche. :) > > > > Another zram-blk's usecase is following as. > > The admin can use it as tmpfs so it could help small memory system. > > The tmpfs is never good solution for swapless embedded system. > > > > Patch 1 adds new Kconfig for zram to use page table method instead > > of copy. > > > > Patch 2 adds more comment for zsmalloc. > > > > Patch 3 moves zsmalloc under mm. > > > > Patch 4 moves zram from driver/staging to driver/blocks, finally. > > Patch 1(suggested by Andrew Morton) and 2(Just comment to make review easy) > are prepartion for promotion so I hope it could be merged into your staging > regardless of allowing promotion at the moment. Sure, I'll be glad to do so, thanks for letting me know. greg k-h -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>