Total used free shared buff/cache available With -m, the results are displayed in MBs instead of KBs. $ swapon -showĪnother useful command is the free command that displays both swap space and memory usage. You can use the swapon -show command to view the swap space on your system. How you can view the amount of swap space on your Linux system? You can test it by running this command: $ sudo pm-hibernate If you get the response shown above, your system is hibernation-ready. To determine if your system can hibernate, run this command: $ which pm-hibernate When you wake it up (e.g., by lifting the 'lid' on a laptop), all the programs you were running return to the state they were in when the system went into hibernation. A system that hibernates saves your system state immediately to the hard disk and powers down. The distinction between swap and swap with hibernation is important. In fact, when a system boots, it moves programs like the kernel and systemd into RAM to get going. Programs and data use RAM because that's the only way they can be processed by the system. In other words, it provides a way to free up RAM on a busy system. It's called 'swap' because the system will move some inactive pages in memory into the swap space so that it can accommodate more data in RAM. It gets used when the system's physical memory (RAM) is full and the system needs more memory resources.

Swap space is disk space that acts something like an extension of memory.

But first, let's review some fundamentals. So let's check out some commands that can help you look into your swap space. Even so, viewing and gauging the adequacy of swap space on a system is not overly complicated, and knowing what's normal for your system can help you spot when something is wrong. Most of us don't often think about swap space unless we run into a problem on our systems that suggests we don't have enough.

Monitor ram usage ubuntu