CentOS 5 :: 0.3% Clock Slowdown In Kernel 2.6.18-238.9.1?
May 4, 2011
I am seeing a 0.3% clock slowdown in kernel 2.6.18-238.9.1.It is giving ntpd conniptions.The problem does not occur in the previous 2.6.18-238.5.1 kernel.
# 2.6.18-238.9.1
[root@blue ~]# uname -a
Linux blue 2.6.18-238.9.1.el5 #1 SMP Tue Apr 12 18:10:13 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux[code]....
I am trying to install vmware server on CentOS: In vmware installation guide it says before intalling:
Before you begin, read the following notes and make adjustments to your host system: The realtime clock function must be compiled in your Linux kernel. The parallel port PCstyle hardware option (CONFIG_PARPORT_PC) must be built and loaded as a kernel module (that is, it must be set to m when the kernel is compiled).
I had cloned a centos 5.6 installation from virtualbox virtual machine to physical box. Everything work fine. However, the time showing in os using date command differs from bios time by roughly 4 hours. I am running ntp services which sync the time with another centos server on the network. It appears that some services are using virtual clock and some use physical clock. How do I get rid of virtual clock and only use physical clock?
I recently added an external hard drive through a IEEE 1394 interface. I'm finding that during large file transfers the system slows to a crawl. It's still running: routing for example seems fine. But running applications are pretty much unusable: Apache is unusably slow, SSH login is very slow, etc. Currently I'm using the IEEE 1394 drivers from Axel's ATRpms but I'm pretty sure I saw this with the default kernel IEEE 1394 drivers too.
I am using AT91SAM9260 and running Linux 2.6.27 on it. Once i sync the Kernel clock and cmos clock with the reference clock and leave it for 1 day, i see a drift of nearly 8-10 sec. The kernel clock is running faster. How can i correct this?
I am using FC 2.6.31 kernel and am tying to bring up a SDIO network card. I am not able to change the SDIO clock speed which is by default 50MHz.I have to bring it down to somewhere around 25Mhz to make the card working smooth.How can we set the host clock speed from our driver in this kernel.
When using make menuconfig - under Device Drivers --> Character Devices --> there should be an option with the label "Enhanced Real Time Clock Support" (CONFIG_JS_RTC).
The problem is that this option seems to only show up while using the menu method when other options are either enabled or disabled and I've entirely forgotten what should be what. I swear fingered it out once.
This is on an older computer (P4) so HPET is no good.
You would think that disabling the HPET option would enable the RTC option but that does not appear to be the case.
I understand I can just add the option to the .config file and avoid this hassle but I'm very interested to know how to make this work.
To show my appreciation I will do something nice for you such as call you a nice name or tell you that you are pretty (or ugly if that's what you prefer).
I wanted to synchronize both clock from windowsxp and centos. whenever i switch to centos i have to change clock before use is there any method so that i can synch both windows clock and centos clock?
I am running a LAMP system with CentOS 5.4.The clock just automatically shifted backwards by 19 hours and 30 minutes crippling some of my reports and probably damaging something else along the way.The router supplying IP to this server is a DD-WRT and shows proper time.By the way what does that mean? time drifted by that 33.667 ms?
I try to setup a HPC cluster with CentOS 5.5. But now there is no Internet connection available in the room where the hardware is located so I set up ntpd server using synchronization with local clock (maybe I do something wrong). Here is my ntp.conf file on a master node (the master node has IP 10.0.1.1, a file server has IP 10.0.1.2 and compute nodes are 10.0.1.3..10.0.1.11, comments are omitted):
I'm having a problem with the time on one of my servers jumping forward into the future. We run serveral CentOS 5.4 servers running Xen, some up to date and some a little older. The one in question is running 2.6.18-164.el5xen, with xen-libs-3.0.3-94.el5_4.2 and xen-3.0.3-94.el5_4.2. On this server are several Xen virtual machines, also running CentOS 5.4 with kernel 2.6.18-164.el5xen. One in particular has problems with the clock keeping proper time.
We use NTP (ntpd) to sync time to a central server in the company. Our NTP set-up works fine, and we have problems on only a couple of servers out of many. The problem I see is that one one particular Xen virtual machine, the clock will suddenly jump forward into the future, usually by several minutes but once by more than an hour. This has obvious implications for software running on the machine. Software such as Oracle grid control agent will restart itself under the (incorrect) assumption that it has been hung for several minutes with no activity. Oracle database will cope gracefully, but applications that refer to the clock will be confused.
We detect these time jumps because we have Nagios checking the clock on each host against the centralised time server (Nagios's check_ntp plugin). Nagios will suddenly report a clock offset that is miles into the future. Following the time jump, ntpd on the host in question will re-sync the time. Ntpd keeps the time steady, ticking just a few milliseconds per second until real time catches up with the server. i.e. Nagios will report the time as being 10 minutes ahead, then a minute later the host will be 9 minutes ahead, and then a further minute later the host will be 8 minutes ahead of real time. The clock on the host stays running very slow until it eventually is correct.
I'm using a very simple conky script to diplay the date and time on my desktop. I've noticed that he conky clock is a few seconds early compared to the time displayed in the right hand side of the top panel (Natty). I guess both displays are based on the same "internal" time, so I'm left wondering how this could happen, and how to sync back the clocks.
It seems that Conky is in sync with the system date, while the panel clock is 2 seconds late (on my system). Checked with while true; do date; sleep 0.1; done
i recently caved and upgraded to ubuntu 11.04, despite my hate of the unity interface. anyway, i seem to be having completely random, massive lag spikes! seems to happen when i do certain things, such as spend to much time on videos, or stream hd videos. playing games, such as minecraft, and using skype seems to be giving me the same issue. i don't know what to do! i haven't found anything similar to this in my google searches,
I am having a bad slowdown issue when I enable Visual Effects with the Ati proprietary drivers that come with the installation. Everything runs very slow maximizing and minimizing take about 3-5 seconds per click and the effects get all choppy and don't look right like they did on my x1950 video card. I have tried downloading the current drivers from the ATI site but they don't seem to be initialising correctly after I perform the install.
I also know that the graphics card is not the culprit as it works perfectly fine on my Windows 7 64 bit install. There is no reason that my video card cannot handle the Visual Effects as it is a 1GB 4890 should have more than enough horsepower.
My machine is:
AMD Phenom II 965 Black Edition 8 GB G. Skill 1600 DDR3 Memory 1 TB Western Digital Caviar hard drive 1 GB 4890 Graphics Card ATI.
Anyone seeing a dramatic slowdown and "PAGE NOT FOUNDS" after the latest updates?
It even happens on LAN activity. Peak speed is excellent, the ability to resolve both local and WAN addresses is very spotty.
Machine is a newer Clone with AMD Phenom II dual core with 2gb running 10.04 32-bit with Gnome. Network is Gigabyte MoBo 1000-T ethernet hardwired to Dlink router into cablemodem.
XP and Win7 aren't affected.
It was ripping this morning, but right now, is pretty much crippled.
I have noticed that when iptables is active on my router i get a noticeable slowdown on browsing. This is untraceable through traceroute:
Code: traceroute -n www.a-site-here.com
finishes immediately and at the same time when loading the site on firefox I am getting timeouts.
I use firewall builder to configure iptables. I have removed all rules while trying to find the one causing the problem, but even disabling all rules does not solve the problem. So, by leaving only an "accept-all" rule on firewall builder(so i don't lock myself outside) I still get slowdowns. In this case
Code: iptables --list-rules gives: Code: -P INPUT DROP -P FORWARD DROP -P OUTPUT DROP
I have Ubuntu 10.04. I installed the KDE libraries to use Okular. Then Ubuntu took almost 30s more to boot (20s black screen between login and desktop). I uninstalled KDE, booted on another kernel, rebooted and the boot time was OK again (25s).
I reinstalled KDE, 55s to boot again. Rebooted couples of times always the same. Rebooted on another kernel then again on mine (it seems to fix the slow boot times).
Boot time was 35s (I thought it was OK). After lauching Okular, the boot time was again 55s...
Removed KDE, Okular, and the boot time is normal again since 10 reboots..
Does anyone else have problems when loading an animated gif in firefox? After upgrading to natty, firefox eats 100% of cpu each time an animated gif is displayed on the tab title, or when the favicon is an animation. I have an fglrx driver, but opengl animation doesnt slowdown pc as much as favicons does on firefox.
So found one issue: When torrent upload speed reaches peak speed (160-200 Kbytes/s) huge read slowdown happens. Server becomes almost unreachable... It allows to connect via putty but it takes a lot of time.
Tested top stats during those lags (Deluge, Transmission) - 10-15% CPU usage.
So I think the problem is in LVM and not in CPU.
How is it possible to find weak place in system to avoid those lags... Cause if torrent is seeding it's impossible to watch movies through network form that server.
after update to kernel-2.6.18-164.el5 one of the 2 NIC's of my machine are only found at 1 of 4 reboots. Using the old one kernel-2.6.18-128.7.1.el5 all is fine. This are the to NIC's:
I compiled my kernel, compiled scsi support into kernel, used the new kernel and initrd, the boot failed.Then ,i unzip my initrd, found that sd_mod.ko can't be insert, i added it manual, and reboot OK.so, why! in the kernel configure , the sd_mod.ko is set to <M> , but why it can't be found in initrd?
The server runs# uname -r2.6.18-128.4.1.el5However, today I executed yum update kernel*due to security advisory. I was just about to reboot the system when I realized that it runs VMWare Server Instance that will most likely fail to restart after kernel upgrade (I had a hard time fixing it after previous kernel update). Now I want to keep 2.6.18-128.4.1.el5 after reboot.I see that new kernel is scheduled for booting:
Does anyone else find that Openoffice 3.2's spreadsheet app becomes unresponsive when copying and pasting multi-cell selections? I've had this problem ever since I started using Ubuntu 10.04, which comes with OO.O 3.2. The problem becomes noticeable whenever I make a selection more than about 8-10 columns across. Once the flashing border appears around the selected cells, the spreadsheet app becomes very sluggish. The mouse still moves normally, but it takes several seconds after a click until the highlight moves to another cell, or to un-select the cells, or copy them. These slowdowns happen both in old spreadsheets and in freshly created ones. They didn't happen with Openoffice 3.1 or earlier. Haven't tried it under Windows, so I'm not sure whether this is an issue specific to Linux OpenOffice 3.2. Other apps don't seem to be affected.
I have a home server based on Ubuntu Linux 10.04.2.
Hardware: Motherboard - Asus AT4NM10-I (Intel NM10, PCI) CPU - Integrated Intel Atom D410 RAM - 2 Gb Lan - D-Link DGE-528T Gigabit Adapter
Provider gives 8/2 Mbit ADSL connection.
So tried Deluge and Transmission, and integrated or external network card and no luck.
When torrent file is being seeded on top speed network starts freezing, server almost unreachable, video freezing when watching it by LAN from server... etc...
When I pause upload - everything starts working ok!
Network based on gigabit switch and cooper UTP cables...
If I initiate a file copy of more than a couple of GiB, the PC goes into a dramatic slowdown. Even selecting a different subdirectory through Nautilus can take 30+ seconds.Now, whilst I appreciate that file copying puts a load on the bus, DMA and, to a certain extent, the CPU, it seems unconscionable that it makes the PC effectively unusable until the copy has completed.Is there any way to (practically) lower the priority, or similar, of the copy process so that one can continue to use the platform during large file copies? Right now, I end up using a laptop adjacent to the PC whenever I have to copy a large file. This, for a mainstream operating system is, frankly, ludicrous.I'm aware that I could run Nautilus 'nicely' but I don't want to make changes which would compromise other aspects of the system. It would also be pleasant, for a change, not to have to read a couple of telephone directories of technical documentation in order to resolve the problem myself. This must be a general problem and, in my view, something which seriously compromises the usefulness of Ubuntu given the sizes of contemporary drives and files.
The i7 I'm using at the moment has 8 cores non of which go over 15% usage while the copy is progressing despite the OS being effectively frozen for long periods.Environment:Intel Core i7-2600 @ 3.40GHz; 16GB RAM; Natty (11.04) fully updated as at 29th July 2011; Kernel 2.6.38-10-generic, GNOME 2.32.1.; Primary drive has 563.9GiB free space, Running in Ubuntu 'Classic' (no effects) mode
Disk /dev/sdc: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes
I'm running 32-bit Debian Squeeze (2.6.32-5-686) on an old IBM TinkCentre piece-meal system that runs great otherwise. I have a LITEON iHAS424 Burner attached. As soon as I insert any disk (CD, DVD, Blank, Commercial, etc.) the system either locks up entirely or crawls to a near stop. The drive is about 3-4 months old and I've experienced the problem a couple of times in the past but just about every time I try to use it lately. The CD/DVD drive seems to work fine on other systems, but I haven't had the luxury of leaving in for any length of time to be 100% sure.
I have been able to pull out of the problem in the past by opening up the case and disconnecting/reconnecting both ends of the drive cable, but this doesn't always work and never "feels right" as a fix.Here is what I think are the significant portions of my messages log file:Quote:
Mar 1 20:03:46 bugs kernel: [ 1.415289] ata_piix 0000:00:1f.2: PCI INT A -> GSI 18 (level, low) -> IRQ 18 Mar 1 20:03:46 bugs kernel: [ 1.415299] ata_piix 0000:00:1f.2: MAP [ P0 P1 IDE IDE ]
I'm running CentOS 5.3 and would like to know what the "best" or "proper" method is to build a custom kernel using the generic kernel sources from kernel.org. Most of the references I've found talk about modifying the current CentOS kernel using the RPM way. I really want to have the latest kernel due to some important security issues that haven't been addressed in the current CentOS 5.3 kernel.