How to display the real-time memory usage in Linux

Often times, we need to monitor our Linux server memory usage, “watch” is a handy command to display the real-time memory usage in Linux.

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watch – execute a program periodically, showing output fullscreen

We can issue the following command to keep track the real time memory usage in Linux.

watch -d free -m

The memory usage will update every 2 seconds, and the different will be highlighted.