Vmware Date/Time Issue

moneyshotz · 07-12-2003, 04:44 AM

Hey Guys,
I have this setup where I have windows as the host and its running Debian as my guest OS on another partition. My question is will VMWARE mess up the time on Linux? Because for some reason the time in windows is fine. But when I'm in Linux it goes incredibly slow...like each computer minute = 3 real mintues. Anyone hear something like this before?

hampel · 07-12-2003, 05:03 AM

I have time problems, too.
But i didn't try to solve it, because it's not my pc;-)

There is running Linux real and Windows on virtual pc.
Windows always shows an other time, but it differes 1-2 hours...

kris.kj.jacobs · 07-12-2003, 07:23 AM

If you have performance problems on your Linux host, search for "performance" on the VMware website. They have some tips and tricks on this. The most important things here are: more RAM makes it go faster, disable /dev/rtc lowers the load on the host computer.

I don't use the build in time synchronization feature of VMware. I use an NTP server on the host computer (Linux) and an NTP client on the guest OS (AtomSync).

Hope it helps.

whansard · 07-12-2003, 08:32 AM

apparently you've solved the equation for time travel.
you move forward in time using linux, and back in time
using windows.
when you listen to music on the radio when running
linux, does it sound really fast?

moneyshotz · 07-12-2003, 01:18 PM

SO what exactly should I do? My host is Windows and my guest is linux. And there's something in VMware where I can fix that? And right now i have 512 total on my machine and Im letting vmware use 256mb.

petcherd · 08-31-2007, 05:00 PM

VMWare has an official whitepaper on time-keeping: http://www.vmware.com/pdf/vmware_timekeeping.pdf

JSkywalker · 11-10-2007, 02:17 PM

anyone got any good links on how to keep track of time in guest OS (linux), running under VMware on linux (openSUSE 10.2)

my system is about 14 seconds too fast in 100 seconds...

i did test this whith the folowing script:

Code:

while true; do /usr/sbin/ntpdate -b <host>; sleep 100; done

where <host> is replaced with the ip-address of the host-os.

results of this are:

Code:

..... ntpdate[123]: step time server <host> offset -14.414969 sec

petcherd · 11-12-2007, 12:28 PM

I've added this to my crontab:
9,19,29,39,49,59 * * * * /usr/local/bin/timecheck

My timecheck script does a /usr/sbin/ntpdate, then parses the output and Emails me if the offset doesn't include the string "0.0" (ie. it notifies me if it tweaked the clock by more than a tenth of a second, though it could be fooled if it had to tweak some multiple of 10 seconds).

Here's the script, sloppy, though it may be:

Code:

#!/bin/bash
ntpdate <host> > /tmp/timesync
#test for precision > tenth of a sec ; otherwise, notify root
if grep "offset 0.0" /tmp/timesync > /dev/null
then
    :
elif grep "offset -0.0" /tmp/timesync > /dev/null
then
    :
else
    cat /tmp/timesync | mail -s "$HOSTNAME timecheck" root
fi
rm /tmp/timesync