Random panics in 11.0 and 12.0 on J1900

[Adam]

On Wed, Jul 10, 2019 at 11:28 AM James Snow <snow at teardrop.org> wrote:

> I have a set of J1900 hosts running 11.0-RELEASE-p1 that experience
> seemingly random panics.


What is the size of this J1900 set? Do you also have J1900 which do not
exhibit the problem?


> One, memtest has turned up no errors on 12.0 host I witnessed the panic
> on.
>

memtest cannot conclusively confirm dimm is good, it is only conclusive on
bad ones.  You can find more info about others learning this lesson
here(see extended comments):

https://superuser.com/questions/547822/how-many-passes-are-enough-with-memtest


> Two, a small number of systems on the same hardware are running
> 10.3-RELEASE, and have experienced no panics in their history. Panics
> have only happened on 11s, and now 12.
>

Once upon a time in a hypothetical universe, I had a stick of ram which
would run on Win98 for very long periods without issue.  It wouldn't even
boot with Win NT.  After the manufacturer sent the same one back twice, I
tased it and RMA'd again.  This time, I got a new stick and all was good.

The point is memory issues can be very subtle and replacing with known good
modules is the easiest way to be sure.

-- 
Adam