[libvirt-users] Monitor guest vm memory usage

Hi All Is there a tool to monitor qemu-kvm guest vm memory usage ( free in guest vm)?Nowadays, I have already researched some methods:1. qemu-kvm process memory usage.     Since qemu-kvm process memory usage always increases as time goes on, it will not reflect the memory usage in vm.2. virsh dommemstat     Just as method 1.3. virsh qemu-monitor-command --hmp [domain name] "info mem"     (1) when guest vm memory size less than 4Gbytes, it will output something like this:            7f882000-7f883000 00001000 urw            7fbf8000-7fbf9000 00001000 urw            88000000-88001000 00001000 -rw            88002000-88003000 00001000 urw            88004000-88005000 00001000 urw            c9000000-c9001000 00001000 urw            e8bfe000-e8bff000 00001000 urw            ea000000-ea001000 00001000 urw            ffbfc000-ffbfd000 00001000 -rw            ffbfe000-ffbff000 00001000 urw           it shows pde info of PG_PRESENT_MASK, maybe has some relation with guest vm memory usage.      (2) when guest vm memory size larger than 4Gbytes, it will output noting. Please help!!