date command counts time quicker than hwclock (RTC)

carl0ski · 12-29-2005, 03:55 AM

On boot i correctly set the CMOS time to

i ran both date and hwclock to check the time.
heres the result

carlos:/home/carl0ski # hwclock &&date
Thu 29 Dec 2005 08:19:44 PM EST -0.504746 seconds
Thu Dec 29 20:20:08 EST 2005

basically same time

i rinsed lathed and repeated here

carlos:/home/carl0ski # date && hwclock
Thu Dec 29 21:19:41 EST 2005
Thu 29 Dec 2005 08:49:31 PM EST -0.139466 seconds

difference blows out to 30 minutes in thirty minutes
(exactly twice as fast)

I have a dual core (dual processor System)
the problem was gone when i parsed notsc and no_timer_check to bios but now it's back

stress_junkie · 12-29-2005, 05:11 AM

Are you using ntp/xntp (Network Time Protocol)? This would check your system time against an accurate time source on the Internet and would create what is called a drift file. This drift file adjusts for the inaccuracy in the operating system's jiffy clock (software clock). Once the xntp daemon has run for a few days and has adjusted your system time numerous times it will make the software clock much more accurate. At that time you can disconnect from the Internet for several days at a time and the software clock will remain fairly accurate. You can find more information about NTP and the xntp software at www.ntp.org. The list of public time servers at this site may be a bit out of date. You can find public time servers for your time zone via Google. I would provide a reference to a good list of public time servers but I didn't bookmark the one that I found.

The hardware clock on WinTel computers is notoriously inaccurate. It amazes me that you can purchase a quartz wristwatch that is accurate to within 1 second in a thousand years for $25 but computer manufacturers refuse to put a good hardware clock in their machines.

carl0ski · 12-29-2005, 05:32 AM

Quote:

Originally Posted by stress_junkie

Are you using ntp/xntp (Network Time Protocol)? This would check your system time against an accurate time source on the Internet and would create what is called a drift file. This drift file adjusts for the inaccuracy in the operating system's jiffy clock (software clock). Once the xntp daemon has run for a few days and has adjusted your system time numerous times it will make the software clock much more accurate. At that time you can disconnect from the Internet for several days at a time and the software clock will remain fairly accurate. You can find more information about NTP and the xntp software at www.ntp.org. The list of public time servers at this site may be a bit out of date. You can find public time servers for your time zone via Google. I would provide a reference to a good list of public time servers but I didn't bookmark the one that I found.

The hardware clock on WinTel computers is notoriously inaccurate. It amazes me that you can purchase a quartz wristwatch that is accurate to within 1 second in a thousand years for $25 but computer manufacturers refuse to put a good hardware clock in their machines.

no i'm not using an NTP services

but also like ive stated perviously the hardware clock is fine

The BIOS time and RTC remain correct (hwclock)
but the kernel pacing and date cause chaos.

Repeat rates on keyboard mouse etc even if set to 1second repeats 2 times in a second.
the clock on the taskbar is fast reboot and it is back to normal (grabs it from BIOS)

i'll check out xntp

wouldnt know if it solves the pacing issue or bandaids by changing the clock back down at intevals