From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by e34.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id l8OLoc1I032209 for ; Mon, 24 Sep 2007 17:50:38 -0400 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v8.5) with ESMTP id l8OLocER488294 for ; Mon, 24 Sep 2007 15:50:38 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l8OLocb4003905 for ; Mon, 24 Sep 2007 15:50:38 -0600 Subject: Re: + maps2-export-page-index-in-kpagemap.patch added to -mm tree From: Dave Hansen In-Reply-To: <20070924213549.GJ19691@waste.org> References: <200709242044.l8OKi01e016834@imap1.linux-foundation.org> <20070924205901.GI19691@waste.org> <1190668988.26982.254.camel@localhost> <20070924213549.GJ19691@waste.org> Content-Type: text/plain Date: Mon, 24 Sep 2007 14:50:36 -0700 Message-Id: <1190670636.26982.258.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Matt Mackall Cc: akpm@linux-foundation.org, wfg@mail.ustc.edu.cn, balbir@linux.vnet.ibm.com, jjberthels@gmail.com, linux-mm List-ID: On Mon, 2007-09-24 at 16:35 -0500, Matt Mackall wrote: > On Mon, Sep 24, 2007 at 02:23:08PM -0700, Dave Hansen wrote: > > Could someone elaborate a little bit more on exactly why you'd want to > > know which parts of the file are mapped? > > Google codesearch finds one actual user of remap_file_pages (and > -lots- of false positives) in an obscure webserver, so I think the > answer somehow involves Oracle. If you're asking yourself wtf Oracle is doing, I can see how this is helpful. But, since Oracle has to maintain its own internal mappings of what it remapped, this shouldn't help Oracle itself. In any case, even if you realize that Oracle is misusing (under-utilizing?) its remapped areas, what do you do? You have to go dig into Oracle to find out what it was doing. That is precisely what you would have had to do in the first place without this patch. I don't quite get what this buys us. -- 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