Tools Commands for monitoring Memory Usage in ubuntu Debian Tools / Commands for monitoring Memory Usage in ubuntu / Debian free - Display amount of free and used memory in the system. watch -n 5 free -m - Real time memory usge vmstat - Report virtual memory statistics top - Show top processes and memory usage htop - interactive process/memory usage viewer cat /proc/meminfo Show memory size and usage. gnome-system-monitor � Graphical tool for viewing process/memory/network usage download file now