* Physical capacity, which is normally the capacity calculated from the SPD data. * Usable capacity, which is the successfully trained memory capacity.
The usable capacity is equal or lower than the physical capacity.
What's the appropriate way of reporting these two capacities in Redfish?
I saw in Redfish schema guide, there are two properties under the Memory Resource. * CapacityMiB - Memory capacity in mebibytes (MiB). * LogicalSizeMiB - Total size of the logical memory in MiB.
I am thinking of using "CapacityMiB" for Physical Capacity (the capacity calculated from the SPD data) and "LogicalSizeMiB" for Usable Capacity (successfully trained memory capacity). Not sure if that's appropriate.
CapacityMiB is certainly the right thing to use to show the physical capacity based on the SPD info.
LogicalSizeMiB was added for alignment with SMBIOS with reporting logical memory devices. SMBIOS defines a logical memory device as: "Logical non-volatile memory devices are not physically installed in the system. Logical memory devices are created using memory capacity from the installed physical volatile memory devices. Logical memory devices are not created from installed physical non-volatile memory devices."
So, specifically for your use case where you want to show "trained capacity", that's not something we report in the model today, and we'll have to discuss this further in the group.