kernel MCA messages

[John Baldwin]

On Tuesday, August 24, 2010 7:13:23 pm Dan Langille wrote:
> On 8/22/2010 9:18 PM, Dan Langille wrote:
> > What does this mean?
> >
> > kernel: MCA: Bank 4, Status 0x940c4001fe080813
> > kernel: MCA: Global Cap 0x0000000000000105, Status 0x0000000000000000
> > kernel: MCA: Vendor "AuthenticAMD", ID 0xf5a, APIC ID 0
> > kernel: MCA: CPU 0 COR BUSLG Source RD Memory
> > kernel: MCA: Address 0x7ff6b0
> >
> > FreeBSD 7.3-STABLE #1: Sun Aug 22 23:16:43
> 
> FYI, these are occurring every hour, almost to the second. e.g. 
> xx:56:yy, where yy is 09, 10, or 11.
> 
> Checking logs, I don't see anything that correlates with this point in 
> the hour (i.e 56 minutes past) that doesn't also occur at other times.
> 
> It seems very odd to occur so regularly.

That is because machine checks for corrected errors have to be polled and the 
kernel polls once an hour.  On newer Intel CPUs (such as Nehalem) there is a 
separate interrupt (CMCI) that can fire for corrected errors.

-- 
John Baldwin