Hello,

192.168.20.139 is a linux with zabbix agent 2.4.7:

/opt/zabbix-2.4.8rc1/bin/zabbix_get -s 192.168.20.139 -k vm.memory.size[pused]
53.858698
/opt/zabbix-2.4.8rc1/bin/zabbix_get -s 192.168.20.139 -k vm.memory.size[pavailable]
85.354566

At doc https://www.zabbix.com/documentation/2.0/manual/appendix/items/vm.memory.size_params , I can read:

The sum of vm.memory.size[used] and vm.memory.size[available] does not necessarily equal total. For instance, on FreeBSD ...

I would like to add what is happening on linux world and make clear that pused + pavailable is not 100%

Thank you !