# Multi-Processing Module prefork

This Multi-Processing Module implements a pre-forking web server.

Status: MPM
Source File: prefork.c
Module Identifier: mpm_prefork_module

## Summary

This Multi-Processing Module (MPM) implements a pre-forking non-threaded web server which handles request in a manner very similar to the default behavior of Apache 1.3 on Unix.

## Directives

- CoreDumpDirectory
- PidFile
- LockFile
- MaxClients
- MaxRequestsPerChild
- MaxSpareServers
- MinSpareServers
- ScoreBoardFile
- StartServers

## MaxSpareServers directive

Syntax: MaxSpareServers number
Default: `MaxSpareServers 10`
Context: server config
Status: core

The MaxSpareServers directive sets the desired maximum number of idle child server processes. An idle process is one which is not handling a request. If there are more than MaxSpareServers idle, then the parent process will kill off the excess processes.

Tuning of this parameter should only be necessary on very busy sites. Setting this parameter to a large number is almost always a bad idea.

See also MinSpareServers and StartServers.

## MinSpareServers directive

Syntax: MinSpareServers number
Default: `MinSpareServers 5`
Context: server config
Status: core

The MinSpareServers directive sets the desired minimum number of idle child server processes. An idle process is one which is not handling a request. If there are fewer than MinSpareServers idle, then the parent process creates new children at a maximum rate of 1 per second.

Tuning of this parameter should only be necessary on very busy sites. Setting this parameter to a large number is almost always a bad idea.

This directive has no effect on Microsoft Windows.

See also MaxSpareServers and StartServers.