System Time Runs Fast for Hyper-V Linux Guest

If you find your Linux guest in a Hyper-V system runs fast, I found about 5 minutes every hour then.

vi /boot/grub/menu.lst

Locate the Kernel that you wish to boot to or on all listed Kernel boot options add:

clock=pit

An example of my menu.lst file as follows. I have added the option to kernel build 2.6.18-164.15.1.el5

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,0)
#          kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00
#          initrd /initrd-version.img
#boot=/dev/sda
default=1
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS (2.6.18-194.3.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-194.3.1.el5 ro root=/dev/VolGroup00/LogVol00 hda=noprobe hdb=noprobe
        initrd /initrd-2.6.18-194.3.1.el5.img
title CentOS (2.6.18-164.15.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-164.15.1.el5 ro root=/dev/VolGroup00/LogVol00 hda=noprobe hdb=noprobe clock=pit
        initrd /initrd-2.6.18-164.15.1.el5.img
title CentOS (2.6.18-164.11.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-164.11.1.el5 ro root=/dev/VolGroup00/LogVol00
        initrd /initrd-2.6.18-164.11.1.el5.img
title CentOS (2.6.18-164.6.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-164.6.1.el5 ro root=/dev/VolGroup00/LogVol00
        initrd /initrd-2.6.18-164.6.1.el5.img
title CentOS (2.6.18-164.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-164.el5 ro root=/dev/VolGroup00/LogVol00
        initrd /initrd-2.6.18-164.el5.img