From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id C47DD6B0260 for ; Wed, 27 Sep 2017 17:46:45 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id a7so25266549pfj.3 for ; Wed, 27 Sep 2017 14:46:45 -0700 (PDT) Received: from out4433.biz.mail.alibaba.com (out4433.biz.mail.alibaba.com. [47.88.44.33]) by mx.google.com with ESMTPS id t63si8090805pfg.128.2017.09.27.14.46.43 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 Sep 2017 14:46:44 -0700 (PDT) From: "Yang Shi" Subject: [PATCH 0/2 v8] oom: capture unreclaimable slab info in oom message Date: Thu, 28 Sep 2017 05:46:14 +0800 Message-Id: <1506548776-67535-1-git-send-email-yang.s@alibaba-inc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, mhocko@kernel.org Cc: Yang Shi , linux-mm@kvack.org, linux-kernel@vger.kernel.org Recently we ran into a oom issue, kernel panic due to no killable process. The dmesg shows huge unreclaimable slabs used almost 100% memory, but kdump doesn't capture vmcore due to some reason. So, it may sound better to capture unreclaimable slab info in oom message when kernel panic to aid trouble shooting and cover the corner case. Since kernel already panic, so capturing more information sounds worthy and doesn't bother normal oom killer. With the patchset, tools/vm/slabinfo has a new option, "-U", to show unreclaimable slab only. And, oom will print all non zero (num_objs * size != 0) unreclaimable slabs in oom killer message. For details, please see the commit log for each commit. Changelog v7 a??> v8: * Adopted Michala??s suggestion to dump unreclaim slab info when unreclaimable slabs amount > total user memory. Not only in oom panic path. Changelog v6 -> v7: * Added unreclaim_slabs_oom_ratio proc knob, unreclaimable slabs info will be dumped when unreclaimable slabs amount : all user memory > the ratio Changelog v5 a??> v6: * Fixed a checkpatch.pl warning for patch #2 Changelog v4 a??> v5: * Solved the comments from David * Build test SLABINFO = n Changelog v3 a??> v4: * Solved the comments from David * Added Davida??s Acked-by in patch 1 Changelog v2 a??> v3: * Show used size and total size of each kmem cache per Davida??s comment Changelog v1 a??> v2: * Removed the original patch 1 (a??mm: slab: output reclaimable flag in /proc/slabinfoa??) since Christoph suggested it might break the compatibility and /proc/slabinfo is legacy * Added Christopha??s Acked-by * Removed acquiring slab_mutex per Tetsuoa??s comment Yang Shi (2): tools: slabinfo: add "-U" option to show unreclaimable slabs only mm: oom: show unreclaimable slab info when unreclaimable slabs > user memory mm/oom_kill.c | 22 ++++++++++++++++++++++ mm/slab.h | 8 ++++++++ mm/slab_common.c | 29 +++++++++++++++++++++++++++++ tools/vm/slabinfo.c | 11 ++++++++++- 4 files changed, 69 insertions(+), 1 deletion(-) -- 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