From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-f70.google.com (mail-lf1-f70.google.com [209.85.167.70]) by kanga.kvack.org (Postfix) with ESMTP id A72EF6B5028 for ; Thu, 30 Aug 2018 03:29:43 -0400 (EDT) Received: by mail-lf1-f70.google.com with SMTP id o4-v6so1573400lfg.11 for ; Thu, 30 Aug 2018 00:29:43 -0700 (PDT) Received: from bastet.se.axis.com (bastet.se.axis.com. [195.60.68.11]) by mx.google.com with ESMTPS id p22-v6si4587937ljj.46.2018.08.30.00.29.41 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 30 Aug 2018 00:29:42 -0700 (PDT) Date: Thu, 30 Aug 2018 09:29:40 +0200 From: Vincent Whitchurch Subject: Re: [PATCH 2/2] scripts: add kmemleak2pprof.py for slab usage analysis Message-ID: <20180830072939.i33m43mj7uslhvmz@axis.com> References: <20180828103914.30434-1-vincent.whitchurch@axis.com> <20180828103914.30434-2-vincent.whitchurch@axis.com> <20180828162804.4ee225124cbde3f39f53fd80@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180828162804.4ee225124cbde3f39f53fd80@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org On Tue, Aug 28, 2018 at 04:28:04PM -0700, Andrew Morton wrote: > On Tue, 28 Aug 2018 12:39:14 +0200 Vincent Whitchurch wrote: > > > Add a script which converts /sys/kernel/debug/kmemleak_all to the pprof > > format, which can be used for analysing memory usage. See > > https://github.com/google/pprof. > > Why is this better than /proc/slabinfo? slabinfo just tells you how much memory is being used in a particular slab, it doesn't give you a breakdown of who allocated all that memory. slabinfo can't also tell you how much memory a particular subsystem is using. For example, here we can see that tracer_init_tracefs() and its callers are using ~12% of the total tracked memory: $ pprof -top -compact_labels -cum prof Showing nodes accounting for 13418.95kB, 92.07% of 14575.28kB total Dropped 4069 nodes (cum <= 72.88kB) flat flat% sum% cum cum% ... 0 0% 56.71% 1832.15kB 12.57% tracer_init_tracefs+0x74/0x1cc And that tracefs' dentrys use 500 KiB and its inodes use 1+ MiB: $ pprof -text -compact_labels -focus tracer_init_tracefs -nodecount 2 prof Main binary filename not available. Showing nodes accounting for 1794.85kB, 12.31% of 14575.28kB total Dropped 1912 nodes (cum <= 72.88kB) Showing top 2 nodes out of 32 flat flat% sum% cum cum% 1294.56kB 8.88% 8.88% 1294.56kB 8.88% new_inode_pseudo+0x8/0x4c 500.29kB 3.43% 12.31% 500.29kB 3.43% d_alloc+0x10/0x78 ... > > > $ ./kmemleak2pprof.py kmemleak_all > > $ pprof -text -ignore free_area_init_node -compact_labels -nodecount 10 prof > > Are we missing an argument here? s/prof/kmemleak_all/? No, the default output filename of this script is called "prof".