virt

virt@lists.centos.org

1 participants
1609 discussions

VMWare Server -- Which Kernel is Best
by John Thomas 09 Feb '08

09 Feb '08

I read http://bugs.centos.org/view.php?id=2189 Summary: CentOS is not getting optimal performance in a virtualized environment and on slow cpus but I am not sure I understand the current best practice. Your thoughts would be appreciated. Options as I see them: 1. Run kernel-vm-2.6.18-53.1.4.el5 with clocksource=pit until the excellent CentOS team builds the latest kernel into a VM kernel (This is working for me now). 2. Run kernel-2.6.18-53.1.6.el5 with divider=10 and hope the clock does not go fast (I have not tried this). -- Sincerely, John Thomas

2 1

Build VirtualBox OSE for CentOS?
by Johnny Hughes 04 Feb '08

04 Feb '08

Is there any need for CentOS to build and distribute the OSE version of VirtualBox? The differences between the versions are here: http://www.virtualbox.org/wiki/Editions The reason I ask is that the Full version is free for personal use and the restrictions (especially no USB or RDP) make the OSE version fairly crippled, so I am not sure there is enough benefit to design and keep updated the OSE RPM packages. What does everyone think? Thanks, Johnny Hughes

3 3

Xen performance (very slow) problem with 4GB of RAM.
by Michael Olson 03 Feb '08

03 Feb '08

I just took the x64 CentOS 5.1/Xen system I've been working on and upgraded from 2GB to 4GB of memory. Fresh minimal install of the OS (to remove some 3.2 stuff I had done trying to make PCI passthrough work). No special options, just a flat out default install. Dom0 is incredibly slow, I haven't tried DomU's yet to see if they are affected. X in particular is impressively slow (you can watch the screen be filled in one little block at a time, with several seconds between blocks) but it's not just video apps, it takes a considerable amount of time for the Xend daemon to start during boot. Before worrying about it I updated everything, same problem. Nothing interesting looking in dmesg or /var/log/messages. I tried out the vanilla kernel and it booted/ran well, no sign of the problem. Next, I tried Dom0 limited to 1.5GB (kernel /xen.gz-2.6.18-53.1.6.el5 dom0_mem=1536M), and it performed well. This workaround is probably adequate for me, I haven't found what the boundary conditions are on the problem and I haven't tested DomU performance yet. A Google and BugTracker search didn't turn this problem described elsewhere, is this known or is this something unique to me? Thanks -- Michael

2 1

Kernel panic in DomU when using swiotlb=force option
by Michael Olson 29 Jan '08

29 Jan '08

I'm trying to get a PVR-150 PCI card imported into a Xen DomU, however the driver blows up the kernel when loaded. The work around for this mentioned in various places is to use swiotlb=force on the DomU kernel. That leads to a fast and furious kernel panic. I've tried this with all Dom0 & DomU running kernel-xen-2.6.18-53.el5 kernel-xen-2.6.18-53.1.6.el5, bot x86 and 86_64 versions, also tried iommu=soft and various sizing options with swiotbl. Any ideas on how to fix or work-around this? Thanks -- Michael Kernel splat: ------------------------------------------------------- [root@hydra mythic]# xm create mythic -c Using config file "./mythic". Started domain mythic Bootdata ok (command line is ro root=LABEL=/1 swiotlb=force) Linux version 2.6.18-53.1.6.el5xen (mockbuild(a)builder6.centos.org) (gcc version 4.1.2 20070626 (Red Hat 4.1.2-14)) #1 SMP Wed Jan 23 11:59:21 EST 2008 BIOS-provided physical RAM map: Xen: 0000000000000000 - 0000000030800000 (usable) No mptable found. Built 1 zonelists. Total pages: 198656 Kernel command line: ro root=LABEL=/1 swiotlb=force Initializing CPU#0 PID hash table entries: 4096 (order: 12, 32768 bytes) Xen reported: 2400.082 MHz processor. Console: colour dummy device 80x25 Dentry cache hash table entries: 131072 (order: 8, 1048576 bytes) Inode-cache hash table entries: 65536 (order: 7, 524288 bytes) ----------- [cut here ] --------- [please bite here ] --------- Kernel BUG at lib/../arch/i386/kernel/swiotlb.c:160 invalid opcode: 0000 [1] SMP last sysfs file: CPU 0 Modules linked in: Pid: 0, comm: swapper Not tainted 2.6.18-53.1.6.el5xen #1 RIP: e030:[<ffffffff80334da7>] [<ffffffff80334da7>] swiotlb_init_with_default_size+0xa0/0x19e RSP: e02b:ffffffff805d9f40 EFLAGS: 00010282 RAX: 00000000fffffff4 RBX: 0000000000000000 RCX: 0000000000063906 RDX: ffffffffff578000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000004000000 R08: 0000000000001000 R09: ffffffff806399e0 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffffffff80599000(0000) knlGS:0000000000000000 CS: e033 DS: 0000 ES: 0000 Process swapper (pid: 0, threadinfo ffffffff805d8000, task ffffffff804c4a00) Stack: 0000000000000295 0000000000020800 0000000000000000 ffffffff80273167 0000000000000000 ffffffff805ec50a 0000000000000000 0000000000020800 0000000000000000 0000000000000000 Call Trace: [<ffffffff80273167>] pci_swiotlb_init+0x9/0x2d [<ffffffff805ec50a>] mem_init+0x5e/0x233 [<ffffffff805e2a7a>] start_kernel+0x189/0x224 [<ffffffff805e21ed>] _sinittext+0x1ed/0x1f3 Code: 0f 0b 68 1b e1 47 80 c2 a0 00 48 83 eb 80 48 8b 05 4c ca 33 RIP [<ffffffff80334da7>] swiotlb_init_with_default_size+0xa0/0x19e RSP <ffffffff805d9f40> <0>Kernel panic - not syncing: Fatal exception -------------------------------------------------------

2 1

Network problems with Centos 5 xen kernel
by Richard Chapman 28 Jan '08

28 Jan '08

Hi - I have a machine which was originally built with Centos 5.0 including xen. It has all the current updates and here are some questions: The current problem is: 1) If I boot the non-xen kernel - it runs fine. If I boot the xen kernel - it boots - but has no network connectivity - and I get the following errors continuously in the messages log: Time/date: C5 Kernel: vif0.0: received packet with own address as source address. And another question: 2) The Centos 5.1 release notes say that the 5.1 xen release includes dnsmasq, and that this may conflict with dhcpd and named if you are running these. I am running both - and i thought dnsmasq was not running because it is set to "not start at boot" - but I now notice that it is "running" even though it is set to "not start on boot". This is true whether I boot the xen or non-xen kernel. Is this a problem - and if so - how do I stop it from running? How do dnsmasq and dhcpd both function without breaking each other? Now some detailed background: The machine uses a Realtek 8111B network adaptor - and this has been a problem all along. I used to manually reinstall the r1000 driver (apparently the correct driver for the adaptor) every time the kernel was updated. Tedious - but it worked. My xen kernel worked fine. Some months back - a bunch of updates came through corresponding to the release of Centos 5.1 - and my normal driver re-install didn't seem to get the Xen kernel running. On advice from the Centos forums - I installed the dkms-r1000 driver - and eventually got the non-xen kernel running fine - but couldn't get the xen kernel running. Every boot - the message "starting eth0 - Failed" would come up. I have been using the non-xen kernel ever since. My system has both kernel-devel and kernel-xen- devel installed. Just yesterday - I installed the latest Kernels ( kernel 2.6.18-53.1.6.el5 <https://192.168.0.201:10000/software/edit_pack.cgi?search=kernel&package=ke…>) - using gnome software updater which installs both xen and non-xen kernels. The non-xen kernel worked fine without any manual driver install. Presumably the dkms install worked fine. When I tried to boot the xen kernel - there were lots of problems - partly because I recently got the shcpd going on the server - and it now needs static ips. The xen kernel still seemed to be set to dynamic ips - but that was easily fixed. Now the message "starting etho - OK" is displayed - and nearly everything looks OK in the startup messages - but several things are slow to start. Once it boots - there is no network connectivity - and the above "vif0.0" errors appear in the messages log. Can anyone shed any light on these questions? Thanks Richard.

1 0

BUG: soft lockup detected on CPU#?
by Brett Worth 22 Jan '08

22 Jan '08

Hello All. I've just started looking into Xen and have a test environment in place. I'm seeing an annoying problem that I thought worthy of a post. Config: I have 2 x HP DL585 servers each with 4 Dual core Opterons (non-vmx) and 16GB RAM configured as Xen servers. These run CentOS 5.1 with the latest updates applied. These system both attach to an iSCSI target which is an HP DL385 running ietd and serving SAN based storage. I have a test VM running CentOS 5.1 also updated. Problem: If I run the VM on a single server everything is OK. If I do a migrate of the VM to the other server I start getting random "BUG: soft lockup detected on CPU#?" messages on the VM console. The messages seem to happen with IO but not every time. A reboot of the VM on the new server will stop these messages. I've also left the VM running overnight a couple of times and when I do I find that any external sessions (ssh) are hung in the morning but the console session is not. New ssh sessions can be started and seem to work. After much googling it looks like the kernel messages can occur if dom0 is very busy but mine is not. Any suggestions? Regards Brett Worth

3 4

Problem with CentOS 5.1 / Xen / Migration : domU time
by Frederic SOULIER 21 Jan '08

21 Jan '08

Hi all, I'm having issue with my Centos 5.1 /Xen installation. I'm having 2 dom0 running 2.6.18-53.1.4.el5xen (x86_64). These two dom0 are connected to a SAN. These two dom0 hosts multiple domU like Centos 4.5 (2.6.9-55.0.9.ELxenU) and Centos 5.1 (2.6.18-53.1.4.el5xen). These two dom0 run ntpd to synchronize dom0 time. When i start a virtual machine on the first dom0 all seems good, the domU time is like the dom0 time. The problem appears when i migrate the domU to another dom0. After the migration, the time in domU on the new dom0 is totally false (we can have more than one day of desynchronisation) and the time on the domU seems to be blocked (the clock indicates always the same time ). In the xend Logs we can't see any error message with the debug mode. The solution for this moment is to restart the domU in the new dom0 to be synchronized again. We manage a lot of authentications services like CAS or Shibboleth which uses timestamp for security validation and this problem is very annoying for us. Anyone has encountered this problem ? Any idea how to solve it ? Thanks for your help. Regards Fred -- Frederic Soulier Administrateur Reseau Centre de Ressources Informatiques Université Toulouse 1 Sciences Sociales 2 RUE DU DOYEN GABRIEL MARTY 31042 TOULOUSE CEDEX 9 Tel : +33 5 61 63 39 98 / +33 5 61 63 39 98 Fax : +33 5 61 63 37 98 Bureau : AR38 bis http://cri.univ-tlse1.fr/

2 2

Centos 4 physical to virtual VMWare
by Ted Miller 14 Jan '08

14 Jan '08

Any tips on taking a Centos 4 desktop from physical hardware to virtual environment? Ted Miller Indiana, USA

2 1

Firewalling domU
by Mindaugas 11 Jan '08

11 Jan '08

Hello, I think I saw this somewhere but cannot find it with google now. How to setup anti-spoofing firewall rules in dom0 so that domU could not change IP and try to get spoof other traffic? I could use physdev module of iptables but how to determine which vif belongs to which domU without too much scripting? Or parsing "xm list" and matching with some configuration file (like: domain1:192.168.1.10 domain2:192.168.1.22) is the way? Then how to automatically run the script after "xm create"? Thanks for the ideas. Question should be simple but I'm stuck here now. :) Mindaugas

1 0

[Fwd: [CentOS-devel] Preview Xen 3.2 rc* packages]
by Karanbir Singh 10 Jan '08

10 Jan '08

FYI -- Karanbir Singh : http://www.karan.org/ : 2522219@icq

1 0

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

virt