Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755570Ab1DGWQw (ORCPT ); Thu, 7 Apr 2011 18:16:52 -0400 Received: from mailout-de.gmx.net ([213.165.64.23]:53747 "HELO mailout-de.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754565Ab1DGWQv (ORCPT ); Thu, 7 Apr 2011 18:16:51 -0400 X-Authenticated: #1474915 X-Provags-ID: V01U2FsdGVkX1/sWV5gpBrsedkw/EKeAkSgOFLT/PivA236lblj5N G5ncOnFi40NC95 Message-ID: <4D9E38CD.2000006@gmx.de> Date: Fri, 08 Apr 2011 00:21:01 +0200 From: Thomas Sattler User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.15) Gecko/20110303 Thunderbird/3.1.9 MIME-Version: 1.0 To: Linux Kernel Mailing List Subject: 2.6.38.x: system hangs, iowait ~75, no resource-hogs, no logs X-Enigmail-Version: 1.1.1 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3711 Lines: 97 Hi there ... I observed three system hangs since 2.6.38 (two times 2.6.38, once 2.6.38.2). I have no idea what triggers the problem, I cannot find the cause myself. I tried these: top: ~~~~ - no cpu-hogg, still a bit free RAM, lots of free SWAP - iowait is constantly high at ~75%, I don't know why dmesg, /var/log/*: ~~~~~~~~~~~~~~~~~~ Nothing in 'dmesg', nothing in the logfiles. pkill / iotop / ps: ~~~~~~~~~~~~~~~~~~~ they all hang quite soon, no reaction on Ctrl-C. While 'ps' shows some lines of output, 'pkill' and 'iotop' just hang. vmstat 1: ~~~~~~~~~ procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 0 4 72 421008 54560 326652 0 0 0 0 518 1293 25 9 0 66 0 4 72 421008 54560 326652 0 0 0 0 311 535 13 4 0 83 2 4 72 420208 54560 326652 0 0 0 0 450 882 18 9 0 73 0 4 72 421008 54560 326652 0 0 0 0 377 914 19 5 0 76 (I collected about 90 lines, there's not much to be seen.) I run 'strace -o dump command' with iotop, ps and su. (And lost a tty to each of them.) $ tail dump_* ==> dump_iotop <== fstat64(9, {st_mode=S_IFREG|0644, st_size=2952, ...}) = 0 mmap2(NULL, 2952, PROT_READ, MAP_SHARED, 9, 0) = 0xb6d80000 _llseek(9, 2952, [2952], SEEK_SET) = 0 munmap(0xb6d80000, 2952) = 0 close(9) = 0 open("/proc/5904/cmdline", O_RDONLY|O_LARGEFILE) = 9 fstat64(9, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0 fstat64(9, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb6d80000 read(9, ==> dump_ps <== stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2309, ...}) = 0 stat64("/proc/5904", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0 open("/proc/5904/stat", O_RDONLY) = 6 read(6, "5904 (thunderbird-bin) D 5900 58"..., 1023) = 242 close(6) = 0 open("/proc/5904/status", O_RDONLY) = 6 read(6, "Name:\tthunderbird-bin\nState:\tD ("..., 1023) = 836 close(6) = 0 open("/proc/5904/cmdline", O_RDONLY) = 6 read(6, ==> dump_su <== stat64("/home/tsattler/.pam_environment", 0xbffdb3e0) = -1 ENOENT (No such file or directory) access("/usr/bin/xauth", X_OK) = 0 setuid32(1000) = 0 chdir("/home/tsattler") = 0 close(3) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb75f3728) = 25247 rt_sigprocmask(SIG_BLOCK, ~[RTMIN RT_1], NULL, 8) = 0 rt_sigaction(SIGTERM, {0x8049ce0, [], 0}, NULL, 8) = 0 rt_sigprocmask(SIG_UNBLOCK, [ALRM TERM], NULL, 8) = 0 waitpid(-1, 'top' showed constantly increasing sysload, I rebooted (via Alt-SysRq-[S][U][B]) at a load of about 25-30. My system is as follows: ~~~~~~~~~~~~~~~~~~~~~~~~ IBM T41p, 1.5GB RAM, 4GB SWAP (nearly unused), two HDs 160/80GB. Gentoo Linux, kernel 2.6.38.2 (vanilla sources). I compiled the kernel myself. I skipped 2.6.37 but run 2.6.36.3 with sabayon's fourth version of a backport of sched-automated-per-session-task-groups.patch for more than two months without any problems. CPU-Speed is 1700MHz (hardware) but I run the machine at 1400MHz most of the time as the fans become loud when running at full speed. ** Please CC: me, as I'm not on the list. ** Thomas -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/