> On Mon, 1 Nov 2010, KOSAKI Motohiro wrote: > > > > The new tunable added in 2.6.36, /proc/pid/oom_score_adj, is necessary for > > > the units that the badness score now uses. We need a tunable with a much > > > > Who we? > > > > Linux users who care about prioritizing tasks for oom kill with a tunable > that (1) has a unit, (2) has a higher resolution, and (3) is linear and > not exponential. No. Majority user don't care. You only talk about your case. Don't ignore end user. > Memcg doesn't solve this issue without incurring a 1% > memory cost. Look at a real. All major distributions has already turn on memcg. End user don't need to pay additional cost. > > > > higher resolution than the oom_adj scale from -16 to +15, and one that > > > scales linearly as opposed to exponentially. Since that tunable is much > > > more powerful than the oom_adj implementation, which never made any real > > > > The reason that you ware NAKed was not to introduce new powerful feature. > > It was caused to break old and used feature from applications. > > > > No, it doesn't, and you completely and utterly failed to show a single > usecase that broke as a result of this because nobody can currently use > oom_adj for anything other than polarization. Thus, there's no backwards > compatibility issue. No. I showed. 1) Google code search showed some application are using this feature. http://www.google.com/codesearch?as_q=oom_adj&btnG=Search+Code&hl=ja&as_package=&as_lang=&as_filename=&as_class=&as_function=&as_license=&as_case= 2) Not body use oom_adj other than polarization even though there are a few. example, kde are using. http://www.google.com/codesearch/p?hl=ja#MPJuLvSvNYM/pub/kde/unstable/snapshots/kdelibs.tar.bz2%7CWClmGVN5niU/kdelibs-1164923/kinit/start_kdeinit.c&q=oom_adj%20kde%205 When you are talking polarization issue, you blind a real. Don't talk your dream. 3) udev are using this feature. It's one of major linux component and you broke. http://www.google.com/codesearch/p?hl=ja#KVTjzuVpblQ/pub/linux/utils/kernel/hotplug/udev-072.tar.bz2%7CwUSE-Ay3lLI/udev-072/udevd.c&q=oom_adj You don't have to break our userland. you can't rewrite or deprecate old one. It's used! You can only add orthogonal new knob. > > > sense for defining oom killing priority for any purpose other than > > > polarization, the old tunable is deprecated for two years. > > > > You haven't tested your patch at all. Distro's initram script are using > > oom_adj interface and latest kernel show pointless warnings > > "/proc/xx/oom_adj is deprecated, please use /proc/xx/oom_score_adj instead." > > at _every_ boot time. > > > > Yes, I've tested it, and it deprecates the tunable as expected. A single > warning message serves the purpose well: let users know one time without > being overly verbose that the tunable is deprecated and give them > sufficient time (2 years) to start using the new tunable. That's how > deprecation is done. no sense. Why do their application need to rewrite for *YOU*? Okey, you will got benefit from your new knob. But NOBDOY use the new one. and People need to rewrite their application even though no benefit. Don't do selfish userland breakage! -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>