f2db8a79_OS_X_Tips_Tweaks_and_Tutorials__What_the_data_means
[Category] Commit Charge (K) [Subcategory] Total [What the data means] 
The total amount of physical memory (RAM) and virtual memory (page file) currently in use, in kilobytes. The more programs, files, and data you have open, the greater your commit charge will be. The greater the commit charge, the more demands will be put on your system. To reduce the commit charge, close programs and files, especially large files.
Windows Task Manager – Performance Monitoring Explained | Windows Vista,XP, Linux and OS X Tips,Tweaks and Tutorials
What the data means