Bug 27933

Summary: Time jitter under load on FreeBSD 4.3 alpha
Product: Base System Reporter: thomas.pornin <Thomas.Pornin>
Component: alphaAssignee: freebsd-alpha (Nobody) <alpha>
Status: Closed FIXED    
Severity: Affects Only Me CC: alpha
Priority: Normal    
Version: 4.3-RELEASE   
Hardware: Any   
OS: Any   

Description thomas.pornin 2001-06-07 13:10:01 UTC 
Under high load, the clock drifts: it slows down. It looses about
20 minutes during a complete "make buildworld" (which takes about 22
hours on that machine).

I installed ntpd; when the machine is idle, everything is fine, but
when there is some load (cpu, disk, memory, I do not know which one is
relevant), ntpd issues messages such as "time reset -1.319533 s" every
20 minutes or so.

(I actually observed that effect with FreeBSD 4.0 to 4.2 on a Multia,
which is supposed to be similar to the AXPpci board)

Fix: 

None included. I can perform a bit of testing, just ask.
How-To-Repeat: 
Deactivate ntpd, setup date and clock, perform a make buildworld, type
"date" afterwards, observe the date shift.
Comment 1 sten 2005-05-23 21:51:59 UTC 
Could you verify that the problem still exists on 5.4-RELEASE ?
Also freebsd now has the hw.timecounter.hardware option, could
you try changing that to one of the other choices ?

-- 
Sten Spans

"There is a crack in everything, that's how the light gets in."
Leonard Cohen - Anthem
Comment 2 Marcel Moolenaar freebsd_committer freebsd_triage 2005-05-24 03:04:47 UTC 
State Changed
From-To: open->feedback

Change state to reflect (re)verification request.
Comment 3 Marcel Moolenaar freebsd_committer freebsd_triage 2005-05-24 03:09:36 UTC 
State Changed
From-To: feedback->closed

Mail bounces. Since this applies to 4.x close the PR.