From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 2CE5E6B004F for ; Tue, 4 Aug 2009 16:24:27 -0400 (EDT) Date: Tue, 4 Aug 2009 13:53:15 -0700 From: Andrew Morton Subject: Re: [PATCH 4/4] tracing, page-allocator: Add a postprocessing script for page-allocator-related ftrace events Message-Id: <20090804135315.b2678e11.akpm@linux-foundation.org> In-Reply-To: <20090804203526.GA8699@elte.hu> References: <1249409546-6343-1-git-send-email-mel@csn.ul.ie> <1249409546-6343-5-git-send-email-mel@csn.ul.ie> <20090804112246.4e6d0ab1.akpm@linux-foundation.org> <20090804195717.GA5998@elte.hu> <20090804131818.ee5d4696.akpm@linux-foundation.org> <20090804203526.GA8699@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Ingo Molnar Cc: penberg@cs.helsinki.fi, a.p.zijlstra@chello.nl, fweisbec@gmail.com, rostedt@goodmis.org, mel@csn.ul.ie, lwoodman@redhat.com, riel@redhat.com, peterz@infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Tue, 4 Aug 2009 22:35:26 +0200 Ingo Molnar wrote: > Did you never want to see whether firefox is leaking [any sort of] > memory, and if yes, on what callsites? Try something like on an > already running firefox context: > > perf stat -e kmem:mm_page_alloc \ > -e kmem:mm_pagevec_free \ > -e kmem:mm_page_free_direct \ > -p $(pidof firefox-bin) sleep 10 > > ... and "perf record" for the specific callsites. OK, that would be useful. What does the output look like? In what way is it superior to existing ways of finding leaks? > this perf stuff is immensely flexible and a very unixish > abstraction. The perf.data contains timestamped trace entries of > page allocations and freeing done. > > [...] > > It would be nice to at least partially remove the vmstat/meminfo > > infrastructure but I don't think we can do that? > > at least meminfo is an ABI for sure - vmstat too really. > > But we can stop adding new fields into obsolete, inflexible and > clearly deficient interfaces, and we can standardize new > instrumentation to use modern instrumentation facilities - i.e. > tracepoints and perfcounters. That's bad. Is there really no way in which we can consolidate _any_ of that infrastructure? We just pile in new stuff alongside the old? The worst part is needing two unrelated sets of userspace tools to access basically-identical things. -- 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