Hello Jerome, On Tue, Dec 03, 2013 at 12:50:24PM +0100, Jerome Marchand wrote: > On 11/25/2013 06:06 AM, Minchan Kim wrote: > > Zram has lived in staging for a LONG LONG time and have been > > fixed/improved by many contributors so code is clean and stable now. > > Of course, there are lots of product using zram in real practice. > > > > The major TV companys have used zram as swap since two years ago > > and recently our production team released android smart phone with zram > > which is used as swap, too and recently Android Kitkat start to use zram > > for small memory smart phone. And there was a report Google released > > their ChromeOS with zram, too and cyanogenmod have been used zram > > long time ago. And I heard some disto have used zram block device > > for tmpfs. In addition, I saw many report from many other peoples. > > For example, Lubuntu start to use it. > > > > The benefit of zram is very clear. With my experience, one of the benefit > > was to remove jitter of video application with backgroud memory pressure. > > It would be effect of efficient memory usage by compression but more issue > > is whether swap is there or not in the system. Recent mobile platforms have > > used JAVA so there are many anonymous pages. But embedded system normally > > are reluctant to use eMMC or SDCard as swap because there is wear-leveling > > and latency issues so if we do not use swap, it means we can't reclaim > > anoymous pages and at last, we could encounter OOM kill. :( > > > > Although we have real storage as swap, it was a problem, too. Because > > it sometime ends up making system very unresponsible caused by slow > > swap storage performance. > > > > Quote from Luigi on Google > > " > > Since Chrome OS was mentioned: the main reason why we don't use swap > > to a disk (rotating or SSD) is because it doesn't degrade gracefully > > and leads to a bad interactive experience. Generally we prefer to > > manage RAM at a higher level, by transparently killing and restarting > > processes. But we noticed that zram is fast enough to be competitive > > with the latter, and it lets us make more efficient use of the > > available RAM. > > " > > and he announced. http://www.spinics.net/lists/linux-mm/msg57717.html > > > > Other uses case is to use zram for block device. Zram is block device > > so anyone can format the block device and mount on it so some guys > > on the internet start zram as /var/tmp. > > http://forums.gentoo.org/viewtopic-t-838198-start-0.html > > > > Let's promote zram and enhance/maintain it instead of removing. > > > > Reviewed-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> > > Acked-by: Nitin Gupta <ngu...@vflare.org> > > Acked-by: Pekka Enberg <penb...@kernel.org> > > Signed-off-by: Minchan Kim <minc...@kernel.org> > > --- > > drivers/block/Kconfig | 2 + > > drivers/block/Makefile | 2 + > > drivers/block/zram/Kconfig | 25 + > > drivers/block/zram/Makefile | 3 + > > drivers/block/zram/zram.txt | 77 +++ > > Shouldn't that go in Documentation/ directory? > In Documentation/blockdev/ maybe.
Sure. I will wait more to get a review from others and I will update it in next spin. Thanks. -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
