similar to: timekeeping on VMware guests

Hi all, If you are using the kernel divider= option in your vmware quest, you are probably aware of the bugs reported at: https://bugzilla.redhat.com/show_bug.cgi?id=315471 Someone @redhat "confirmed" the fix is in the test kernel -92. I tried it but it seems to have the same problem as before - when used with clocksource=pit, it hangs on bootup. Wonder if some of you can test this

Stan, Thanks for the reply. In our case we have actually already done most of the work you suggested to no avail. We had rebuilt two new ntp servers that sync against two stratum 1 sources, and all our nfs clients, regardless of using dovecot, sync to those two machines. You bring up the difference between bare metal and hypervisor, and we are running these machines on vmware 4.0. All the

Hello, I was thinking of creating a wiki page about Xen clocksources and timekeeping.. including dom0, PV guests and HVM guests. Dan and Jeremy: You guys might have some ideas for this page.. please let me know your thoughts :) Subjects to cover: - Xen hypervisor clocksources (hpet, acpi_pm, pit) - Xen dom0 clocksource, ntpd, etc - Xen PV guest clocksources, independent_wallclock, ntpd,

Running Dovecot 2.0.8 on 32bit Centos5.5. The machine is a VMWare ESX VM. I'm seeing a lot of warning messages in syslog as follows: 2011-01-14T11:45:37.315917+08:00 imap4 dovecot: imap: Warning: Time jumped forwards 105 seconds 2011-01-14T11:46:00.598006+08:00 imap4 dovecot: imap: Warning: Time jumped forwards 106 seconds 2011-01-14T11:46:25.364405+08:00 imap4 dovecot: imap: Warning: Time

This is really stupid question. But referring to: http://lists.centos.org/pipermail/centos/2009-October/083791.html I don't see any line related to ntpd in my /var/log/messages . Do I need to turn-on ntpd for timekeeping on VMs? Some people say not to use ntpd on VMs for timekeeping or is it ntpdate cron job? Can someone please elaborate on this? Thanks, Jonathan. -------------- next part

Hi everyone, I have been struggling with having the clock of Linux VM's (including CentOS 4.6 and 5.1) running very fast under VMWare, no matter what I have tried. My platform: - AMD Turion X2 TL-60 - AMD 690 chipset with integrated Radeon x1250 (probably doesn't concern in this case) - Windows Vista Ultimate x64, all Windows Update patches loaded (no SP1 yet) - 4GB RAM - VMWare

On 03/03/16 09:18, Patrick Masotta wrote: >>>> How so? > > it says they cannot emulate the timer interrupt very well; > that's what I understood... If it's the VMware document I'm thinking of (titled "Timekeeping in VMware Virtual Machines"), then the issue is that emulating the timer interrupt can cause a heavy load on the host if the guest timer is

People at vmware have provided patches for RHEL 5 that aim to fix timekeeping issues in vmware guests. https://bugzilla.redhat.com/show_bug.cgi?id=463573 Description of problem (excerpt) : "In a virtual environment, timekeeping for RHEL 64 bit kernels can be problematic, since time is kept by counting timer interrupts for this kernel. The problem arises when the VM is descheduled for some

On 03/01/16 21:11, H. Peter Anvin via Syslinux wrote: > On 03/01/16 07:21, Patrick Masotta via Syslinux wrote: >> >> At the moment I'm seeing timing issues on TFTP transfers (lwIP depends >> on the new interrupt based timer). I have consistently detected >> >> multiple Requests, double ACKs, etc. All these problems seem to be >> >> sourced on the

Before 6.X Syslinux used a "Tick-less" timekeeping approach implemented in /core/bios.inc 6.X now implements a "Tick-counting" strategy (timer interrupt) implemented in /core/timer.inc I think this change presents issues when Sysylinux runs on Virtual Machines emulating a BIOS environment as they cannot correctly emulate the timer interrupt; see VMware's pdf:

On 03/03/16 07:31, Patrick Masotta wrote: > > The timer interrupt works fine in at least KVM, Xen, VMware, and > > Hyper-V. (I've tested iPXE in all of those virtual environments, and > > iPXE relies on the timer interrupt actually triggering a call to an ISR > > within the VM.) > > Well, that contradicts what the VMware document says. How so? Michael

We've noticed our fully-virtualized KVM guests' time keeps getting faster, despite running ntpd. A quick google reveals this to be a known problem with virtual guests. It seems there are a variety of solutions, some apparently vendor-specific. What is the best practice as of now for KVM guests? * Setting independent_wallclock=1 (or is that a xen-only thing)? * Passing kernel

https://bugs.freedesktop.org/show_bug.cgi?id=98709 Bug ID: 98709 Summary: [NV50] clocksource: timekeeping watchdog on CPU2: Marking clocksource 'tsc' as unstable because the skew is too large Product: Mesa Version: 12.0 Hardware: x86-64 (AMD64) OS: Linux (All) Status:

In 780427f0e11 (Indicate that clock was set in the pvclock gtod notifier), logic was added to pass a CLOCK_WAS_SET notification to the pvclock notifier chain. While that patch added a action flag returned from accumulate_nsecs_to_secs(), it only uses the returned value in one location, and not in the logarithmic accumulation. This means if a leap second triggered during the logarithmic

> Date: Fri, 17 Feb 2012 12:06:05 +0000 > From: Ian Campbell <Ian.Campbell@citrix.com> > To: Qrux <qrux.qed@gmail.com> > Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com> > Subject: Re: [Xen-devel] Xen domU Timekeeping (a.k.a TSC/HPET issues) > Message-ID: <1329480365.3131.50.camel@zakaz.uk.xensource.com> > Content-Type:

Reduce special casing of xen_cpuid() by using cpu capabilities instead of faked cpuid nodes. This cleanup enables us remove the hypervisor specific set_cpu_features callback as the same effect can be reached via setup_[clear|force]_cpu_cap(). Removing the rest faked nodes from xen_cpuid() requires some more work as the remaining cases (mwait leafs and extended topology info) have to be handled

Reduce special casing of xen_cpuid() by using cpu capabilities instead of faked cpuid nodes. This cleanup enables us remove the hypervisor specific set_cpu_features callback as the same effect can be reached via setup_[clear|force]_cpu_cap(). Removing the rest faked nodes from xen_cpuid() requires some more work as the remaining cases (mwait leafs and extended topology info) have to be handled

From: David Vrabel <david.vrabel@citrix.com> The high resolution timer code gets notified of step changes to the system time with clock_was_set() or clock_was_set_delayed() calls. If other parts of the kernel require similar notification there is no clear place to hook into. Add a clock_was_set atomic notifier chain (clock_was_set_notifier_list) and call this in place of clock_was_set().

Dear all, I am using R CMD SHLIB to compile a c++ code into a library (.so) and dyn.load to load this library into a R code. I am facing some problems in the c++ code that I can not figure out how to solve. Do you recomend any good way to debug this R + C++ program? If I was programming only in C++ I would use GDB. I would much appreciate any help or suggestion! Best regards, Charles -- Um

I'm running VMware Server 1.0.6 on a CentOS 5.2 host and am having some clock difficulties. Host OS is x86_64 running on 1.9 GHz AMD Sempron, nVidia chipset. Guest OS's are 32-bit FreeBSD (clock works fine after disabling ACPI, setting the clock source to the PIT, and running the guest tools), WinXP (unknown clock status), and i686 CentOS 5.2 (here is the problem). I've tried pretty