[18.04 certification] R740xd Memory Info Fails; nvdimm mismatch

[Michael Reed]

This test is currently failing on the R740xd

Check amount of memory reported by meminfo against DMI

Results:
 /proc/meminfo reports: 62.43GiB
 lshw reports: 80GiB

FAIL: Meminfo reports 18864824320 less than lshw, a difference of 21.96%. Only a variance of 10% in reported memory is allowed.

[Jeff Lane  (bladernr)]

This may be innocuous, or you may have bad ram. This is saying that the system has 80 GiB of RAM installed physically but the kernel is only addressing roughly 62.3GiB.

There is often a small amount of overhead in RAM, and also depending on the system there may be an arbitrary amount of system RAM reserved for an onboard video device.

I'd start by verifying that one of the above isn't the case.

a dmesg dump would be useful too.

[Jeff Lane  (bladernr)]

So, a dmesg dump after a fresh boot (or maybe /var/log/dmesg would suffice). that dump is not useful, unfortunately, as all the important data has already been popped off of the ring buffer.

[Jerry Clement (jerry-clement)]

We resolved the mismatch by removing an NVDIMM placed into the system by another engineer. We should test with NVDIMM again to confirm and resolve.

[Michael Reed (mreed8855)]

We can retest the system on 18.04.1 with the latest SRU updates.

[Jeff Lane  (bladernr)]

That's interesting to note. NVDIMMs do change the parameter of this test. Please do confirm this behaviour (per Jerry's comment from last June).