* KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> [2011-01-31 08:58:53]: > On Fri, 28 Jan 2011 09:20:02 -0600 (CST) > Christoph Lameter <cl@xxxxxxxxx> wrote: > > > On Fri, 28 Jan 2011, KAMEZAWA Hiroyuki wrote: > > > > > > > I see it as a tradeoff of when to check? add_to_page_cache or when we > > > > > are want more free memory (due to allocation). It is OK to wakeup > > > > > kswapd while allocating memory, somehow for this purpose (global page > > > > > cache), add_to_page_cache or add_to_page_cache_locked does not seem > > > > > the right place to hook into. I'd be open to comments/suggestions > > > > > though from others as well. > > > > > > I don't like add hook here. > > > AND I don't want to run kswapd because 'kswapd' has been a sign as > > > there are memory shortage. (reusing code is ok.) > > > > > > How about adding new daemon ? Recently, khugepaged, ksmd works for > > > managing memory. Adding one more daemon for special purpose is not > > > very bad, I think. Then, you can do > > > - wake up without hook > > > - throttle its work. > > > - balance the whole system rather than zone. > > > I think per-node balance is enough... > > > > > > I think we already have enough kernel daemons floating around. They are > > multiplying in an amazing way. What would be useful is to map all > > the memory management background stuff into a process. May call this memd > > instead? Perhaps we can fold khugepaged into kswapd as well etc. > > > > Making kswapd slow for whis "additional", "requested by user, not by system" > work is good thing ? I think workqueue works enough well, it's scale based on > workloads, if using thread is bad. > Making it slow is a generic statement, kswapd is supposed to do background reclaim, in this case a special request for unmapped pages, specifically and deliberately requested by the admin via a boot option. -- Three Cheers, Balbir -- 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>