If you wish to monitor the performance of an OS X system, Apple provides a number of utilities with the operating system to allow you to monitor CPU, memory, and network utilization as well as other system parameters. The Activity Monitor found in
Applications/Utilities provides a graphical user interface
(GUI) for monitoring CPU, memory, and, to a limited extent, network
utilization. The top command found on Linux systems is also
present and provides a command line tool for monitoring memory and CPU
utilization. For network monitoring, there is also the
Network Utility in
Applications/Utilities.
