When loading data, you can view processor and I/O activity. Different operating systems provide different tools for viewing system performance. For example, the Task Manager in Windows enables you to view processor and memory usage and processes.
For more details on:
Windows XP, use Control Panel, then Administrative Tools, and then Performance
Windows Server 2008, use Control Panel, then Administrative Tools, and then Reliability and Performance Monitor
Windows 7, use Control Panel, then Administrative Tools, then Performance Monitor, and then Resource Monitor
Among the tools available on UNIX are top and vmstat; iostat is the most commonly used utility to monitor I/O activity. You can also use third-party tools to view and analyze system use.