To find out what’s using up all virtual memory in a Linux system, you can use the top or htop command.
top provides an overview of system processes and system resource usage, including virtual memory usage. By default, top sorts processes by CPU usage, but you can sort by memory usage by pressing the M key.
htop is an alternative to top that provides a more user-friendly interface and additional features. You can sort processes by memory usage by pressing the F6 key and selecting the MEM% option.
Both top and htop display the total amount of virtual memory available and used in the system, so you can easily see which processes are consuming the most memory.
Another tool that can help you identify processes that are consuming large amounts of virtual memory is smem, which provides a summary of memory usage by process and by user. To install smem, you can use the package manager for your Linux distribution. For example, on Debian-based systems, you can run:
sudo apt-get install smem
Once smem is installed, you can use the following command to show memory usage by process:
smem -k
This will show a table of processes and the amount of virtual memory they are using, ordered by the amount of memory they are consuming.