I monitor value from
/proc/meminfo file, namely the
MemTotal: number. It changes if a ram module breaks, roughly by size of the memory module - this is obvious.
I know the definition for the field from kernel documentation:
MemTotal: Total usable ram (i.e. physical ram minus a few reserved bits and the kernel binary code)
dmesg also lists kernel data. What other particular actions make the
MemTotal number change if I omit hardware failure of the memory module?
This happens on both physical & virtual systems. I monitor hundreds of physical, thousands of virtual systems. Although the change is rather rare, it does happen.