From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 091A66B004F for ; Tue, 23 Jun 2009 20:08:20 -0400 (EDT) Subject: Re: [PATCH] Hugepages should be accounted as unevictable pages. From: Alok Kataria Reply-To: akataria@vmware.com In-Reply-To: <1245800490.31856.21.camel@nimitz> References: <20090623093459.2204.A69D9226@jp.fujitsu.com> <1245732411.18339.6.camel@alok-dev1> <20090623135017.220D.A69D9226@jp.fujitsu.com> <20090623141147.8f2cef18.kamezawa.hiroyu@jp.fujitsu.com> <1245736441.18339.21.camel@alok-dev1> <4A41481D.1060607@redhat.com> <1245793331.24110.33.camel@alok-dev1> <1245795352.17685.31312.camel@nimitz> <1245795823.24110.48.camel@alok-dev1> <1245800490.31856.21.camel@nimitz> Content-Type: text/plain Date: Tue, 23 Jun 2009 17:08:34 -0700 Message-Id: <1245802114.24110.80.camel@alok-dev1> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Dave Hansen Cc: Rik van Riel , KAMEZAWA Hiroyuki , KOSAKI Motohiro , LKML , Lee Schermerhorn , Mel Gorman , "linux-mm@kvack.org" List-ID: On Tue, 2009-06-23 at 16:41 -0700, Dave Hansen wrote: > On Tue, 2009-06-23 at 15:23 -0700, Alok Kataria wrote: > > > Could you just teach the thing to which you are hinting that it also > > > needs to go look in sysfs for huge page counts? > > > > :) yeah i could do that too...the point is that its a module and the > > function to get the hugepages count is not exported right now. I could > > very well add this as an exported symbol and use it from there, but > > there can be someone who doesn't want symbols to be unnecessarily > > exported if their is no in-tree modular usage of that symbol. > > Hmmm. So what is the module doing? The ol', "try to get as much memory > as I possibly can" game? :) > > It sounds like you can get access to the vm statistics from existing > exported symbols, but the stats don't give you quite the info that you > need. > So, you're trying to change things that you *can* get access to. :) Not entirely, I thought that UNEVICTABLE by definition should consider hugepages too. > > We do export all this stuff to userspace. We export all of the huge > page sizes and how many pages are reserved, used, and allocated in each, > plus the contentious Unevictable. Could you just do this calculation in > userspace and pass it into the module with a modparam or sysfs file? Hmm...lets see, I will look to moving that to userspace or something. But irrespective of my need, we must clear the confusion around what unevictable should actually mean. I am biased towards getting hugepages accounted in that :), but what do others think ? Lee, I will let you take a decision on that, if the current semantics look okay, it would be great if you could update the unevictable_lru documentation about this being just the number of pages on unevictable_lru. Thanks, Alok > > -- Dave > -- 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/ . Don't email: email@kvack.org