Linux Kernel in a Nutshell

Name

SMP — Symmetric multi-processing support

This enables support for systems with more than one CPU. If you have a system with only one CPU, like most personal computers, say no. If you have a system with more than one CPU, say yes.

If you say no here, the kernel will run on single and multiprocessor machines, but will use only one CPU of a multiprocessor machine. If you say yes here, the kernel will run on many, but not all, singleprocessor machines. On a singleprocessor machine, the kernel will run faster if you say no here.

Note that if you say yes here and choose architecture 586 or Pentium under Processor family, the kernel will not work on 486 architectures. Similarly, multiprocessor kernels for the PPro architecture may not work on all Pentium based boards.

See also Documentation/smp.txt, Documentation/i386/IO-APIC.txt, Documentation/nmi_watchdog.txt, and the SMP-HOWTO available at http://www.tldp.org/docs.html#howto.