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large clock skew on linux guest under centos 5

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I'm having horrible clock skew issues with VMWare Server 1.04 running on a 64-bit CentOS 5.1 host  (10GB RAM, 8 processing cores) and a 32-bit 2-proc 2GB CentOS 5.1 guest. 

 

Both the server and guest are barely utilized (I'm still in the testing phase).  I recognize that clock skew is par for the course with full-virtualization solutions (and worse with SMP), but this seems excessive.

 

I'd appreciate any suggestions you could offer.

 

Here's /var/log/messages from running ntpdate (ntpdate -s example.com) every 10 seconds via a bash script (the skew keeps killing off the ntpd daemon):

 

Jan 28 13:25:26 guest-vm ntpdate[2554]: step time server 64.25.87.54 offset 7.710381 sec

Jan 28 13:25:46 guest-vm ntpdate[2556]: step time server 64.25.87.54 offset 8.812336 sec

Jan 28 13:25:59 guest-vm ntpdate[2559]: step time server 64.25.87.54 offset 2.063628 sec

Jan 28 13:26:05 guest-vm ntpdate[2561]: step time server 64.25.87.54 offset -5.211154 sec

Jan 28 13:26:19 guest-vm ntpdate[2565]: step time server 64.25.87.54 offset 1.677524 sec

Jan 28 13:26:33 guest-vm ntpdate[2571]: step time server 64.25.87.54 offset 5.063104 sec

Jan 28 13:26:36 guest-vm ntpdate[2573]: step time server 64.25.87.54 offset 1.572231 sec

Jan 28 13:26:53 guest-vm ntpdate[2575]: step time server 64.25.87.54 offset 7.623636 sec

Jan 28 13:26:56 guest-vm ntpdate[2577]: step time server 64.25.87.54 offset 1.427536 sec

Jan 28 13:27:10 guest-vm ntpdate[2579]: step time server 64.25.87.54 offset 4.343356 sec

Jan 28 13:27:13 guest-vm ntpdate[2581]: step time server 64.25.87.54 offset 1.185097 sec

Jan 28 13:27:28 guest-vm ntpdate[2583]: step time server 64.25.87.54 offset 6.050440 sec

Jan 28 13:27:31 guest-vm ntpdate[2588]: step time server 64.25.87.54 offset 1.395005 sec

Jan 28 13:27:31 guest-vm ntpdate[2587]: adjust time server 64.25.87.54 offset 0.153568 sec

 

I've tried booting with "clock=pmtmr" and "clock=pit".  All power saving is disabled on the host and the guest.  I have tools.syncTime = "TRUE" in the vmx for this guest (and vmware tools installed on the guest).  However, I don't know if this is actually used since I don't have X installed.  Also, this would, at most, correct my clock every 1 minute, and with these skews, that could lead to the clock being off by over 90 seconds.

 

Here's some info on the interrupts on the guest:

 

user@guest-vm $ cat /etc/issue && uname -a && /sbin/hwclock && date && cat /proc/interrupts && sleep 10 && cat /proc/interrupts && date && /sbin/hwclock && date

 

CentOS release 5 (Final)

Kernel \r on an \m

 

Linux guest-vm 2.6.18-53.1.6.el5 #1 SMP Wed Jan 23 11:30:20 EST 2008 i686 i686 i386 GNU/Linux

Mon 28 Jan 2008 01:04:49 PM EST  -0.104885 seconds

Mon Jan 28 13:04:47 EST 2008

CPU0       CPU1

0:      97505          0    IO-APIC-edge  timer

1:          8          1    IO-APIC-edge  i8042

6:          4          0    IO-APIC-edge  floppy

7:          0          0    IO-APIC-edge  parport0

8:          2          0    IO-APIC-edge  rtc

9:          0          0   IO-APIC-level  acpi

12:        104          3    IO-APIC-edge  i8042

15:        590        128    IO-APIC-edge  ide1

169:      10282        444   IO-APIC-level  ioc0

177:        570        831   IO-APIC-level  vmxnet ether

185:         21          9   IO-APIC-level  vmxnet ether

NMI:          0          0

LOC:      97266      96300

ERR:          0

MIS:          0

CPU0       CPU1

0:     107528          0    IO-APIC-edge  timer

1:          8          1    IO-APIC-edge  i8042

6:          4          0    IO-APIC-edge  floppy

7:          0          0    IO-APIC-edge  parport0

8:          2          0    IO-APIC-edge  rtc

9:          0          0   IO-APIC-level  acpi

12:        104          3    IO-APIC-edge  i8042

15:        685        128    IO-APIC-edge  ide1

169:      10290        444   IO-APIC-level  ioc0

177:        643        831   IO-APIC-level  vmxnet ether

185:         21          9   IO-APIC-level  vmxnet ether

NMI:          0          0

LOC:     107287     106321

ERR:          0

MIS:          0

Mon Jan 28 13:04:57 EST 2008

Mon 28 Jan 2008 01:05:13 PM EST  -0.942595 seconds

Mon Jan 28 13:04:58 EST 2008


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