Added in Peek-a-Boo 2.6 was the System Information Window, a convenient way to keep an eye on system-wide resource information without using a lot of screen real estate.
You can view the System Information Window by choosing it from Peek-a-Boo's File menu, or using the command-3 key combination.
Peek-a-Boo 2.8.3 added to the Process Information Window: each virtual CPU core in your computer has its own little graph, then there is a cumulative graph for overall CPU usage. (This screenshot was taken while using a dual-core Mac.)
You can drag the System Information Window to an out-of-the-way location on your screen and keep vital information visible.
If your computer is running slowly, the two major culprits are the processor(s) and the memory. The System Information Window shows you at a glance when the CPU is tapped out and when memory is full. (The VM thrash badge will flicker yellow and red when virtual memory is active -- another indication that you're using a lot of memory.)
Process Information Windows, CPU Usage History Windows, and Logging Windows allow you to watch information about individual processes, and even log information to a file if necessary.
You can open a Process Information Window for a process to see a wide selection of information about a process. Along with the icon, name, pid, cpu usage, and memory usage, you can see the full command used when the process was invoked. This can be very helpful for diagnosing daemons or other Darwin utilities.
You can click on the “Show Open Files” button to toggle a slide-out drawer that shows all files and sockets that the process current is using.
CPU Usage History windows allow you to watch a process’ CPU usage over a window of time. This graph scrolls slowly to the left, giving you a chance to glance at the processor-usage characteristics over the last little bit.
When you open a CPU Usage History window, either from the menu or from the main window’s toolbar, a window like the above window will open for the selected process. Peek-a-Boo remembers which process is being watched is stored, so in the future, when that process runs, Peek-a-Boo will display the CPU Usage History window for that process. (To make Peek-a-Boo forget about a given CPU Usage History window, close the window. Then Peek-a-Boo won’t include that window in its periodic search any more.)
There are two percentages you can see: pinned to the upper border is the fullscale percentage; depending on your settings, this may change. The other percentage bounces around with the latest data point so you can easily tell the most recent percentage reading.
You can adjust some CPU Usage History window options; see the preferences page for information about changing how CPU Usage History windows look and behave.
You can monitor several pieces of process information simultaneously for a given process with Logging windows.
Logging windows allow you to track common process information that changes frequently, including the amount of CPU time that the process has used, the amount of physical memory the process is using, and the amount of virtual memory the process is using. You can also log “delta” values for each of these, and an optional timestamp.
The logging information can be written to a file. This file holds tab-delimited fields of everything that the log window shows. Every time a process is logged, Peek-a-Boo creates a new log file with an autogenerated name; the path and name are shown in the Logging window’s title bar.
You can adjust several Logging window parameters, including the frequency with which it updates, and which fields are logged, in the preferences.
Logging windows only add logging lines (i.e. data points) when something that they’re logging is updated.