Code:
proxmox-ve: 5.3-1 (running kernel: 4.15.18-11-pve)
pve-manager: 5.3-9 (running version: 5.3-9/ba817b29)
pve-kernel-4.15: 5.3-2
pve-kernel-4.15.18-11-pve: 4.15.18-33
pve-kernel-4.15.18-9-pve: 4.15.18-30
corosync: 2.4.4-pve1
criu: 2.11.1-1~bpo90
glusterfs-client: 3.8.8-1
ksm-control-daemon: 1.2-2
libjs-extjs: 6.0.1-2
libpve-access-control: 5.1-3
libpve-apiclient-perl: 2.0-5
libpve-common-perl: 5.0-46
libpve-guest-common-perl: 2.0-20
libpve-http-server-perl: 2.0-11
libpve-storage-perl: 5.0-38
libqb0: 1.0.3-1~bpo9
lvm2: 2.02.168-pve6
lxc-pve: 3.1.0-3
lxcfs: 3.0.3-pve1
novnc-pve: 1.0.0-2
proxmox-widget-toolkit: 1.0-22
pve-cluster: 5.0-33
pve-container: 2.0-34
pve-docs: 5.3-2
pve-edk2-firmware: 1.20181023-1
pve-firewall: 3.0-17
pve-firmware: 2.0-6
pve-ha-manager: 2.0-6
pve-i18n: 1.0-9
pve-libspice-server1: 0.14.1-2
pve-qemu-kvm: 2.12.1-1
pve-xtermjs: 3.10.1-1
qemu-server: 5.0-46
smartmontools: 6.5+svn4324-1
spiceterm: 3.0-5
vncterm: 1.5-3
zfsutils-linux: 0.7.12-pve1~bpo1
I use RAID 1 ZFS
Installed 4x LXC
1. LXC load memory 200 MiB
2. LXC load memory 150 MiB
3. LXC load memory 110 MiB
4. LXC load memory 200 Mib
2x KVM
1. KVM load memory 1.2 GiB (Debian adapted from ISPadmin https://www.ispadmin.eu/en/ )
2. KVM load memory 1.3 GiB (win 7)
Why Ram usage is 16.18 GiB