From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id 8FFAF8D0039 for ; Fri, 28 Jan 2011 10:20:06 -0500 (EST) Date: Fri, 28 Jan 2011 09:20:02 -0600 (CST) From: Christoph Lameter Subject: Re: [PATCH 3/3] Provide control over unmapped pages (v4) In-Reply-To: <20110128165605.3cbe5208.kamezawa.hiroyu@jp.fujitsu.com> Message-ID: References: <20110125051003.13762.35120.stgit@localhost6.localdomain6> <20110125051015.13762.13429.stgit@localhost6.localdomain6> <20110128064851.GB5054@balbir.in.ibm.com> <20110128165605.3cbe5208.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: Minchan Kim , balbir@linux.vnet.ibm.com, linux-mm@kvack.org, akpm@linux-foundation.org, npiggin@kernel.dk, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kosaki.motohiro@jp.fujitsu.com List-ID: 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. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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: email@kvack.org