xfce4-cpuload-plugin is a XFCE4 plugin for monitoring CPU usage, supporting multiple cores.
The plugin is the one with 3 bars. The red bar is the overall cpu load and the other two blue bars are each core load.
This plugin was merged into XFCE 4 cpugraph plugin. Development of this plugin is stopped, please see the XFCE cpu graph plugin for same functionality.
Download source-code: xfce4-cpuload-plugin-0.0.1.tar.bz2