System Information
On Windows NT and higher the System Information entry in the View menu and typing Ctrl+I opens a dialog box that shows global system performance metrics like those shown in Task Manager. The information includes the amount of committed and available virtual and physical memory as well as paged and nonpaged kernel buffer usage.
Graphs show the CPU usage history of the system as well as the committed virtual memory usage, I/O usage, and on Windows Vista or higher systems GPU graphs shows GPU utilization and memory usage history. Red in the CPU usage graph indicates CPU usage in kernel-mode whereas green is the sum of kernel-mode and user-mode execution. When committed virtual memory reaches the system Commit Limit, applications and the system become unstable. The Commit Limit is the sum of most of physical memory and the sizes of any paging files. In the I/O graph the blue line indicates total I/O traffic, which is the sum of all process I/O reads and writes, between refreshes and the pink line shows write traffic.
When you move the mouse over the CPU graph a popup displays either on the far left or right of the graph that shows the CPU usage and name of the process that had the largest contribution to CPU usage at the corresponding point in time, as well as the time of the point. Similarly, time stamp information for a point is shown in the Commit graph. Finally, on the I/O graph the tooltip shows the process performing the most I/O at the time of the point, including the amount of data it read and wrote. The popups update as data moves under the mouse, but you can freeze a popup by left clicking and the move the mouse to unfreeze the popup.
On systems with multiple CPUs the System Information dialog includes a Show one graph per CPU checkbox. Checking it switches the display into a per-processor view. Hyperthreaded (SMT) processors sharing the same core and NUMA processors sharing the same node are grouped together and the mouse tooltip shown when hovering over a graph displays the processor and core or node numbers. Note that the mouse tooltips for a processor graph show the name of the process that consumed the most CPU on the entire system at the associated time, not the process that consumed the most CPU on the particular CPU.