From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 6 Oct 2008 11:09:55 +0100 From: Mel Gorman Subject: Re: [PATCH 2/2] Report the pagesize backing a VMA in /proc/pid/maps Message-ID: <20081006100955.GB10212@csn.ul.ie> References: <1223052415-18956-1-git-send-email-mel@csn.ul.ie> <1223052415-18956-3-git-send-email-mel@csn.ul.ie> <20081004221339.GA20175@x200.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20081004221339.GA20175@x200.localdomain> Sender: owner-linux-mm@kvack.org Return-Path: To: Alexey Dobriyan Cc: akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com, dave@linux.vnet.ibm.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On (05/10/08 02:13), Alexey Dobriyan didst pronounce: > On Fri, Oct 03, 2008 at 05:46:55PM +0100, Mel Gorman wrote: > > This patch adds a new field for hugepage-backed memory regions to show the > > pagesize in /proc/pid/maps. While the information is available in smaps, > > maps is more human-readable and does not incur the cost of calculating Pss. An > > example of a /proc/self/maps output for an application using hugepages with > > this patch applied is; > > > > 08048000-0804c000 r-xp 00000000 03:01 49135 /bin/cat > > 0804c000-0804d000 rw-p 00003000 03:01 49135 /bin/cat > > 08400000-08800000 rw-p 00000000 00:10 4055 /mnt/libhugetlbfs.tmp.QzPPTJ (deleted) (hpagesize=4096kB) > > > To be predictable for parsers, the patch adds the notion of reporting on VMA > > attributes by appending one or more fields that look like "(attribute)". This > > already happens when a file is deleted and the user sees (deleted) after the > > filename. The expectation is that existing parsers will not break as those > > that read the filename should be reading forward after the inode number > > and stopping when it sees something that is not part of the filename. > > Parsers that assume everything after / is a filename will get confused by > > (hpagesize=XkB) but are already broken due to (deleted). > > Looks like procps will start showing hpagesize tag as a mapping name > (apologies for pasting crappy code): > Looks that way. How about....