From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f43.google.com (mail-pa0-f43.google.com [209.85.220.43]) by kanga.kvack.org (Postfix) with ESMTP id 378166B0253 for ; Wed, 29 Jul 2015 15:08:09 -0400 (EDT) Received: by pacan13 with SMTP id an13so10255289pac.1 for ; Wed, 29 Jul 2015 12:08:09 -0700 (PDT) Received: from mail-pa0-x229.google.com (mail-pa0-x229.google.com. [2607:f8b0:400e:c03::229]) by mx.google.com with ESMTPS id cl3si11299121pad.39.2015.07.29.12.08.07 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 29 Jul 2015 12:08:08 -0700 (PDT) Received: by pachj5 with SMTP id hj5so10001094pac.3 for ; Wed, 29 Jul 2015 12:08:07 -0700 (PDT) Date: Wed, 29 Jul 2015 12:08:05 -0700 (PDT) From: David Rientjes Subject: Re: hugetlb pages not accounted for in rss In-Reply-To: <20150729005332.GB17938@Sligo.logfs.org> Message-ID: References: <55B6BE37.3010804@oracle.com> <20150728183248.GB1406@Sligo.logfs.org> <55B7F0F8.8080909@oracle.com> <20150728222654.GA28456@Sligo.logfs.org> <20150729005332.GB17938@Sligo.logfs.org> MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="397176738-1464267060-1438196886=:24373" Sender: owner-linux-mm@kvack.org List-ID: To: =?UTF-8?Q?J=C3=B6rn_Engel?= Cc: Mike Kravetz , "linux-mm@kvack.org" , linux-kernel This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --397176738-1464267060-1438196886=:24373 Content-Type: TEXT/PLAIN; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT On Tue, 28 Jul 2015, Jorn Engel wrote: > Well, we definitely need something. Having a 100GB process show 3GB of > rss is not very useful. How would we notice a memory leak if it only > affects hugepages, for example? > Since the hugetlb pool is a global resource, it would also be helpful to determine if a process is mapping more than expected. You can't do that just by adding a huge rss metric, however: if you have 2MB and 1GB hugepages configured you wouldn't know if a process was mapping 512 2MB hugepages or 1 1GB hugepage. That's the purpose of hugetlb_cgroup, after all, and it supports usage counters for all hstates. The test could be converted to use that to measure usage if configured in the kernel. Beyond that, I'm not sure how a per-hstate rss metric would be exported to userspace in a clean way and other ways of obtaining the same data are possible with hugetlb_cgroup. I'm not sure how successful you'd be in arguing that we need separate rss counters for it. --397176738-1464267060-1438196886=:24373-- -- 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