4.8 "Alternate system clock has died" error

[Uwe Doering]

John Baldwin wrote:
> On Friday 18 November 2005 10:05 pm, Charles Sprickman wrote:
> 
>>I tried this query on -stable, hoping someone here can help me further
>>understand and troubleshoot this.
>>
>>Reference:
>>http://thread.gmane.org/gmane.os.freebsd.stable/32837
>>
>>In short, top, ps report 0% CPU on all processes as of a few weeks ago.
>>"systat -vmstat" hands out the "Alternate system clock has died" error.
>>
>>Box is running 4.8-p24 and has been up 425 days.  Nothing out of the
>>ordinary except for the above symptoms.  In searching the various
>>lists/newsgroups, it seems that the other folks with this problem have
>>fixed it in various ways:
>>
>>-early 4.x users referenced a PR that was committed before 4.8
>>-some 5.3 users reported this with unknown resolution/cause
>>-sending init a HUP was suggested (tried it, no luck)
>>-setting kern.timecounter.method: 1 (tried it, no luck)
>>-one user seemed to actually have a dead timer
> 
> Actually, there was a patch that was committed in 5.4 and 6.0 for this issue.  
> You can see the diff here:
> 
> http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/i386/isa/clock.c.diff?r1=1.213&r2=1.214&f=h
> 
> That patch would probably backport to 4.x fairly easily.

I just looked at RELENG_4, and yes, backporting should be easy.  Though 
I haven't tried it yet on our machines.

I wonder, however, what's writing to the RTC on a running server.  Could 
this event perhaps have been triggered by the recent Daylight Saving 
Time switch?

    Uwe
-- 
Uwe Doering         |  EscapeBox - Managed On-Demand UNIX Servers
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