SysPeek is a system monitoring application which enables viewing information about CPU, memory, disk utilization, as well as network traffic from the Ubuntu system tray. This app indicator applet displays a CPU indicator on the system tray which turns blood red when the CPU usage is 100%. This can be helpful in identifying resource intensive software and to check if your system is being hanged due to excessive CPU utilization.
You can click on the CPU usage indicator to get information regarding your CPU and memory usage (including swap memory), network (sent and received kilobytes) and launch System Monitor for further analysis. The CPU usage indicator can be handy to monitor CPU usage particularly during system hangs, when it is hard to open System Monitor instantly.
You can download the .Deb package from the Launchpad link given below and install this application from the Ubuntu Software Center by double clicking on the Deb file.