From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stanislav Meduna Subject: SLAB leaks filep in 3.4.13-rt21 with PREEMPT_RT_FULL Date: Sat, 20 Oct 2012 17:48:09 +0200 Message-ID: <5082C7B9.9010502@meduna.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: linux-rt-users@vger.kernel.org Return-path: Received: from www.meduna.org ([92.240.244.38]:42322 "EHLO meduna.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752001Ab2JTQOC (ORCPT ); Sat, 20 Oct 2012 12:14:02 -0400 Received: from dial-95-105-165-4-orange.orange.sk ([95.105.165.4] helo=[192.168.130.22]) by meduna.org with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.72) (envelope-from ) id 1TPbHZ-0006no-Iq for linux-rt-users@vger.kernel.org; Sat, 20 Oct 2012 17:48:20 +0200 Sender: linux-rt-users-owner@vger.kernel.org List-ID: Hi, compiling a current (a few days back) linux-stable-rt.git with PREEMPT_RT_FULL results in a significant memory leak. Just repeating cat /proc/meminfo | grep Unreclaim shows the unreclaimable memory jumping in 4 - 12 kB steps. sync ; echo 3 > /proc/sys/vm/drop_caches does not help either, this is for sure a real leak. Looking at the slabtop output the "filp" is responsible for most of the allocations, but there are more, even the "pid" is rising although the number of threads in the system stays the same. PREEMPT_LL and selecting the SLUB (which is the preferred allocator but not available with PREEMPT_RT_FULL) solves the problem. I did not test with LL and SLAB (yet - I think that it is hardly improbable that the SLAB allocator is the reason). I can't test with PREEMPT_RTB as this option looks even more broken on my setup and oopses at root filesystem (ext3) mounting so I do not have the logs and the beginning rolls out of the console so I can't even photograph it :( The machine is an industrial embedded PC running a Geode LX. I did not change the kernel in any way except adding an own module that was not loaded during the tests. I am new to linux-rt and this list - is it OK to attach full .config files? Thanks -- Stano