4.3.3. Performance

To a user, performance means quick execution of commands. To a system manager, on the other hand, it means much more: the system admin has to optimize system performance for the whole system, including users, all programs and daemons. System performance can depend on a thousand tiny things which are not accounted for with the time command:

• the program executing is badly written or doesn't use the computer appropriately

• access to disks, controllers, display, all kinds of interfaces, etc.

• reachability of remote systems (network performance)

• amount of users on the system, amount of users actually working simultaneously

• time of day

• ...