Windows Task Manager - Performance Explained
Video notes:
If the Total Commit Charge exceeds the Total Physical Memory, you probably need more RAM. When the Commit Charge is regularly higher than the Physical Memory available, it means that you have to regularly use a Page File, which may slow down your system down if its old. Buy more RAM in that case.
If the Peak Commit Charge is frequently at or near the Limit Commit Charge, you need to increase your memory. When this occurs, it means that your PC is frequently out of memory or close to being out of memory. Either add RAM or increase your Page File size.