Red Hat Bugzilla – Bug 166130
system time drifting on IBM X445
Last modified: 2014-10-19 19:08:33 EDT
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Description of problem:
The system time lags about 16s daily compared with hardware time.
Compared with the greenwich time, the hw time is more accurate.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. a fresh installation of RHEL 3 U5, RHEL 4 U1 or RHEL 2.1 U4.
2. hwclock --systohc
3. compare the system time with hardware time after 24 hours
Actual Results: The system time lags about 16s everyday.
This problem has been reproduced on 3 IBM X445 servers.
The BIOS has been updated to the latest.
It mentioned that the lastest BIOS fixed a time syncronizing problem.
Created attachment 117822 [details]
customer record the hardware time and system time in every 10 minutes.
hardare time system time
2005-08-05 16:00:01 2005-08-05 16:00:00.778561
I see no reason that this is a kernel-utils bug. Refiling against kernel.
Hello, Dawson. Why do you think this is a software problem? Do the
hardware specs guarantee a clock frequency accuracy of <16 secs/day?
Can you use NTP to keep the time-of-day in sync with a more accurate
The hardware drifting time is less than 2s/day compared the Greenwich time.
I have already suggested customer to use NTP and time base.
Customer wants Red Hat to confirmation that this is a hardware problem.
My impression is that the hardware clock interrupt frequency is not
typically guaranteed to be more accurate than the drift you're seeing.
You should run NTP to sync with a machine having a more accurate time base.
Closing as NOTABUG.