From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756543Ab2LGP0e (ORCPT ); Fri, 7 Dec 2012 10:26:34 -0500 Received: from mailout-de.gmx.net ([213.165.64.22]:54305 "HELO mailout-de.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756505Ab2LGP0d (ORCPT ); Fri, 7 Dec 2012 10:26:33 -0500 X-Authenticated: #4463548 X-Provags-ID: V01U2FsdGVkX1+TI3Zg8lOT86vgeST3rhjsnoNCqGW/sDRKtfXka0 4gTaRtVi9ih42I Date: Fri, 7 Dec 2012 17:26:27 +0200 (EET) From: Dimitrios Apostolou X-X-Sender: jimis@soupermouf To: Jan Kara cc: linux-kernel@vger.kernel.org, Roland Eggner , Catalin Marinas , "Theodore Ts'o" Subject: Re: backing up ext4 fs, system unresponsive, thrashing like crazy even though swap is unused In-Reply-To: <20121206164312.GB21029@quack.suse.cz> Message-ID: References: <1353851735.22969.18.camel@soupermouf> <1353871800.22969.28.camel@soupermouf> <20121206142044.GB18547@quack.suse.cz> <20121206164312.GB21029@quack.suse.cz> User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jan, thanks for your help, with this commit I can't reproduce the problem. The problematic workload is no more inflating the ext4_inode_cache, in fact I've been able to run even heavier workloads with the ext4_inode_cache never surpassing 2-4MB. Thanks everyone for helping, Dimitris On Thu, 6 Dec 2012, Jan Kara wrote: > On Thu 06-12-12 17:15:37, Dimitrios Apostolou wrote: >> On Thu, 6 Dec 2012, Jan Kara wrote: >>> On Sun 25-11-12 21:30:00, Dimitrios Apostolou wrote: >>>> On Sun, 2012-11-25 at 15:55 +0200, Dimitrios Apostolou wrote: >>>>> on an old PIII-500MHz laptop, 128MB RAM, kernel 3.6.6, I started a >>>>> backup process (tar|xz -4, nice'd and ionice'd -c3) from ext4 on local >>>>> ATA disk to ext3 on external USB disk (USB-2.0 port on PCMCIA card). >>>>> Even though earlier system load was minimal, free memory was plenty, the >>>>> system now is unresponsive and is thrashing the disk, but the swapfile >>>>> is rarely touched. >>>> >>>> I'm now having the same experience even though I replaced xz (which >>>> needed ~50MB RAM) with gzip. Even though I feel the realtime root shell >>>> is a bit more responsive than before, the OOM killer is out killing >>>> small processes like syslog-ng and systemd-logind... The >>>> ext4_inode_cache slab is taking almost all my memory (117MB). Please >>>> advise! >>> Hmm, it seems commit 4eff96dd5283a102e0c1cac95247090be74a38ed might be >>> interesting for you. It landed in -stable kernels recently as well if I >>> remember right... >> >> Thanks, I appreciate your help as I'm stuck in a dead end now, and >> I've been trying to write some debug hook that prints all >> ext4_inodes and the reason they are pinned (is there an easy way to >> find this out?). >> >> So maybe there is a typo in the SHA1 sum you provided? Gitweb can't >> find it in Linus' tree. > Strange. You are right gitweb doesn't show the SHA1 but I can see it in > my git repo I pulled from Linus. Anyway, I've attached the fix for your > convenience. > > Honza > > -- > Jan Kara > SUSE Labs, CR >