From mboxrd@z Thu Jan 1 00:00:00 1970 From: "SourceForge.net" Subject: [ kvm-Bugs-2351676 ] Guests hang periodically on Ubuntu-8.10 Date: Tue, 13 Jan 2009 19:11:46 +0000 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" To: noreply@sourceforge.net Return-path: Received: from ch3.sourceforge.net ([216.34.181.60]:12105 "EHLO ch3.sourceforge.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750825AbZAMTLt (ORCPT ); Tue, 13 Jan 2009 14:11:49 -0500 Sender: kvm-owner@vger.kernel.org List-ID: Bugs item #2351676, was opened at 2008-11-26 18:59 Message generated for change (Comment added) made by poelzi You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=2351676&group_id=180599 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: Chris Jones (c_jones) Assigned to: Nobody/Anonymous (nobody) Summary: Guests hang periodically on Ubuntu-8.10 Initial Comment: I'm seeing periodic hangs on my guests. I've been unable so far to find a trigger - they always boot fine, but after anywhere from 10 minutes to 24 hours they eventually hang completely. My setup: * AMD Athlon X2 4850e (2500 MHz dual core) * 4Gig memory * Ubuntu 8.10 server, 64-bit * KVMs tried: : kvm-72 (shipped with ubuntu) : kvm-79 (built myself, --patched-kernel option) * Kernels tried: : 2.6.27.7 (kernel.org, self built) : 2.6.27-7-server from Ubuntu 8.10 distribution In guests * Ubuntu 8.10 server, 64-bit (virtual machine install) * kernel 2.6.27-7-server from Ubuntu 8.10 I'm running the guests like: sudo /usr/local/bin/qemu-system-x86_64 \ -daemonize \ -no-kvm-irqchip \ -hda Imgs/ndev_root.img \ -m 1024 \ -cdrom ISOs/ubuntu-8.10-server-amd64.iso \ -vnc :4 \ -net nic,macaddr=DE:AD:BE:EF:04:04,model=e1000 \ -net tap,ifname=tap4,script=/home/chris/kvm/qemu-ifup.sh The problem does not happen if I use -no-kvm. I've tried some other options that have no effect: -no-kvm-pit -no-acpi The disk images are raw format. When the guests hang, I cannot ping them, and the vnc console us hung. The qemu monitor is still accessible, and the guests recover if I issue a system_reset command from the monitor. However, often, the console will not take keyboard after doing so. When the guest is hung, kvm_stat shows all 0s for the counters: efer_relo exits fpu_reloa halt_exit halt_wake host_stat hypercall +insn_emul insn_emul invlpg io_exits irq_exits irq_windo largepage +mmio_exit mmu_cache mmu_flood mmu_pde_z mmu_pte_u mmu_pte_w mmu_recyc +mmu_shado nmi_windo pf_fixed pf_guest remote_tl request_i signal_ex +tlb_flush > 0 0 0 0 0 0 0 +0 0 0 0 0 0 0 0 +0 0 0 0 0 0 0 0 +0 0 0 0 0 0 gdb shows two threads - both waiting: c(gdb) info threads 2 Thread 0x414f1950 (LWP 422) 0x00007f36f07a03e1 in sigtimedwait () from /lib/libc.so.6 1 Thread 0x7f36f1f306e0 (LWP 414) 0x00007f36f084b482 in select () from /lib/libc.so.6 (gdb) thread 1 [Switching to thread 1 (Thread 0x7f36f1f306e0 (LWP 414))]#0 0x00007f36f084b482 +in select () from /lib/libc.so.6 (gdb) bt #0 0x00007f36f084b482 in select () from /lib/libc.so.6 #1 0x00000000004094cb in main_loop_wait (timeout=0) at /home/chris/pkgs/kvm/kvm-79/qemu/vl.c:4719 #2 0x000000000050a7ea in kvm_main_loop () at /home/chris/pkgs/kvm/kvm-79/qemu/qemu-kvm.c:619 #3 0x000000000040fafc in main (argc=, argv=0x7ffff9f41948) at /home/chris/pkgs/kvm/kvm-79/qemu/vl.c:4871 (gdb) thread 2 [Switching to thread 2 (Thread 0x414f1950 (LWP 422))]#0 0x00007f36f07a03e1 in +sigtimedwait () from /lib/libc.so.6 (gdb) bt #0 0x00007f36f07a03e1 in sigtimedwait () from /lib/libc.so.6 #1 0x000000000050a560 in kvm_main_loop_wait (env=0xc319e0, timeout=0) at /home/chris/pkgs/kvm/kvm-79/qemu/qemu-kvm.c:284 #2 0x000000000050aaf7 in ap_main_loop (_env=) at /home/chris/pkgs/kvm/kvm-79/qemu/qemu-kvm.c:425 #3 0x00007f36f11ba3ea in start_thread () from /lib/libpthread.so.0 #4 0x00007f36f0852c6d in clone () from /lib/libc.so.6 #5 0x0000000000000000 in ?? () Any clues to help me resolve this would be much appreciated. ---------------------------------------------------------------------- Comment By: Daniel Poelzleithner (poelzi) Date: 2009-01-13 20:11 Message: I have a very simelar setup. Host: Ubuntu 8.10. Kernel 2.6.28-2-server KVM: 72, 80, 81, 82, 83 tried (using the up to date kvm module, too) Guests: Endian Firewall (centos based.) Kernel 2.6.22.19-72.endian15 Is stable so far. sometimes loos usb devices Ubuntu 8.10 Kernel 2.6.27, 2.6.28-2-server, 2.6.28 vanilla home brew Very unstable. As the Ubuntu 8.10 is also unstable when using the 2.6.28 vanilla kernel, i'm not so sure it's a guest problem. I will now compile a 2.6.28 kernel not having any kvm guest support. Things doesn't seem to have a affect: - using ide instead of virtio - using e1000 instead of virtio however, it seems that it may be caused by io access, but is not reproducable easily. Last tries i did': using kernel parameters "clocksource=acpi_pm notsc" in the guest. Still investigating if it makes the guest stable. btw. with kvm-82 i saw arround 100 io_exits when only the crashed ubuntu 8.10 is running. nothing else. ---------------------------------------------------------------------- Comment By: Chris Jones (c_jones) Date: 2008-12-10 21:29 Message: Actually, I was too quick to say that a Fedora 8 guest is stable. Even there, I'm seeing hangs once I get my application fully installed (basically, once I introduce some load). I also did an update to kvm-80 and the problem still exists (on all the guests I've tried). That's with kvm-80 kernel modules and the kvm-80 user, running on linux-2.6.27.8. Thanks, Chris ---------------------------------------------------------------------- Comment By: Chris Jones (c_jones) Date: 2008-12-01 20:09 Message: Alexey, Thanks for the response. As you advised, I tried a Fedora 8 guest, and it does seem to be much more stable. However, I really need a Debian base system for my application. Not necessarily Ubuntu 8.10, but I haven't had much luck with others either. Do you have any recommendations on one that is particularly stable? Over the weekend I tried: Fedora 8 : Seems very stable, but I really need a debian base. Ubuntu 8.04LTS : Same periodic hangs I was seeing on 8.10 Debian 4.0 Etch: Seems stable on the guest, but on the host, qemu process is running 100% busy while the guest is idle. Any chance you know a workaround for the issue I'm seeing on etch, or can recommend a Debian base distribution which works well with KVM? Thanks much, Chris ---------------------------------------------------------------------- Comment By: Technologov (technologov) Date: 2008-11-27 13:54 Message: In my opinion it is not the Ubuntu host that is problematic - but the guest on KVM. I mean that Ubuntu 8.10 guest is unstable on KVM. I have not found out why. If you try some better tested guest (Fedora 7/8 or Windows XP guest it should be lots more stable). And if you try some other host (i.e. Fedora host and run Ubuntu 8.10 guest it will be unstable). In short - in my opinion - the problem is not host OS, but either KVM or it's connection with guest OS. -Alexey E. "Technologov", 27.11.2008. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=2351676&group_id=180599