mpr(4) SAS3008 Repeated Crashing

[Steven Hartland]

On 04/03/2016 10:58, Borja Marcos wrote:
>> On 04 Mar 2016, at 10:16, Steven Hartland <killing at multiplay.co.uk> wrote:
>>
>> Its very rare but we've also seen this type of behaviour from a failing Intel CPU. There was no other indication the CPU had an issue, which one might expect, so just wanted to make you aware of the possibility.
>>
>> That said the most common cause of this we've seen, when its not a common disk or disks, is a bad backplane or cabling to the backplane.
> Now I’m really curious!
>
> How did you determine that it was the CPU? And what kind of issue was it causing? Noise in the power rails? Interference?
After a month or so of fixing mfi so it recovered from all bad events 
and prevented all the various kernel panics, the machine stayed running 
long enough to log an MCA which pointed to a failing CPU cache.

We we're lucky it was CPU #2 so we disabled all cores for said CPU in 
/boot/loader.conf and all the issues disappeared. We replaced the CPU 
and no more issues.

We we're in the same situation as you, two machines identical configs, 
one which was constantly panicing in mfi the other was rock solid.

     Regards
     Steve