ECC on VM yet again

[YujiTFD]

Greetings, I hope everybody are having good holidays! :)

I have browsed this forum looking for a solid answer, but either I'm blind or there is none. My ESXi-based homelab rig (see the sig) is running TrueNAS SCALE, and watching a related YouTube video I realised I see no "ECC" mention by total RAM amount in the dashboard. ESXi's smbiosDump returns ECC support for all slots, but TrueNAS'es dmidecode -t 16 returns "None":

ESXi smbiosDump

TrueNAS dmidecode -t 16

Physical Memory Array (Type 16): #42 Use: 0x03 (System memory) Location: 0x03 (Motherboard) Slots: 2 Max. Size: 128 GB ECC: 0x06 (Multi-bit) Memory Device (Type 17): #43 Location: "P1-DIMMA1" Bank: "P0_Node0_Channel0_Dimm0" Manufacturer: "Samsung" Serial: "3196305F" Asset Tag: "P1-DIMMA1_AssetTag (date:16/07)" Part Number: "M393A2G40EB1-CPB" Memory Array: #42 Form Factor: 0x09 (DIMM) Type: 0x1a (DDR4) Type Detail: 0x0080 (Synchronous) Data Width: 64 bits (+8 ECC bits) Size: 16 GB Max. Speed: 2133 MT/s Rank: 2 Configured Speed: 2133 MT/s

root@ts[~]# dmidecode -t 16 # dmidecode 3.3 Getting SMBIOS data from sysfs. SMBIOS 2.7 present. Handle 0x0014, DMI type 16, 23 bytes Physical Memory Array Location: System Board Or Motherboard Use: System Memory Error Correction Type: None Maximum Capacity: 25 GB Error Information Handle: Not Provided Number Of Devices: 64 root@ts[~]#

How do I interpret these outputs:
- I do have ECC, it doesn't translate to TrueNAS SCALE, therefore, it does not being utilised,
- I do have ECC, it doesn't translate to TrueNAS SCALE, but still being utilised on ESXi layer, just doesn't shown,
- I do have ECC, which does translate to TrueNAS SCALE and being utilised, just doesn't shown,

Which one of these is TRUE?

Thank you in advance!

Edit: typos.

 

[Arwen]

The answer is likely:

- I do have ECC, it doesn't translate to TrueNAS SCALE VMs, but still being utilised on ESXi layer, just doesn't shown,

Do any VMs show ECC memory?

 

[YujiTFD]

The answer is likely:


Do any VMs show ECC memory?

Checked my Ubuntu VM - same output, no ECC support, all memory bank are "Unknown" :(
Now I'm looking into ESXi issues regarding ECC info passthrough.
On the othe hand, same question about Proxmox hypervisor has been aswered, basicly: "Don't sweat it, hardware does it all", so, maybe, everything is fine as it is.

UPDATE: VeryZ in https://forum.level1techs.com/t/ecc-detection-in-kvm-guest/133209/3 specifically stated, that ESXi does not release ECC counters into emulated layers, so +1 to the "It works on hardware level".