1, create 1 VM with 8G ram and install ubuntu live server 22.04, and install "guest additions", check the addition successfully installed and work fine;
2, full clone it and discard any net card MAC, generating new UUID for disk, and modify the ram to 6G.
3, start both of the VMs, wait them all start up finish
4, click at one VM, and switch to the "Activity" pane, see that ram usage diagram is updated well;
4, switch to the other VM, still on "Activity pane", see that "ram usage" diagram was not updated to correct value, showing those of previous VM.
5, switch to "Tools", and to "Activities" pane, from the activities overview pane, see that the 2 VMs' ram usages are showing correct value.
Note that the 1st VM that I clicked to view "Activity" shows the correct info, and the 2nd shows incorrect.