Isn pre-emptive multitasking slow?
On RISC OS (eg, using a task window or wimp2), yes. On systems designed for it, like Linux, it actually makes the system faster and more responsive. • Multitasking is used when you have more runnable processes than CPUs. Most systems only have 1 CPU. • A runnable process is one which wants to use the CPU (not just a program which is loaded but doing nothing). • Most of the time, nothing is runnable (the computer is waiting for you to do something). In that case, it doesn’t matter which system is used. • Most of the rest of the time, exactly one process is runnable (eg, when you press a key your word processor needs to run to insert the character). When only one process is runnable, it doesn’t matter which system is used. The one runnable process is always chosen. • The only time the type of multi-tasking makes any difference at all is when you have several programs all trying to do things at once (eg, printing, rendering an image and checking your email). In the rare case when you have
