Red Hat ENTERPRISE LINUX 3 Reference Manual page 146

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For more on this topic, refer to the following documentation on the Apache Software Foundation's
website:
• http://httpd.apache.org/docs-2.0/mod/mpm_common.html#listen
•
http://httpd.apache.org/docs-2.0/mod/core.html#servername
10.2.1.2. Server-Pool Size Regulation
When the Apache HTTP Server accepts requests, it dispatches child-processes or threads to handle
them. This group of child processes or threads is known as a server-pool. Under Apache HTTP Server
2.0, the responsibility for creating and maintaining these server-pools has been abstracted to a group
of modules called Multi-Processing Modules (MPMs). Unlike other modules, only one module from
the MPM group can be loaded by the Apache HTTP Server. There are three MPM modules that ship
with 2.0: ,
prefork
available, although the
The original Apache HTTP Server 1.3 behavior has been moved into the
MPM accepts the same directives as Apache HTTP Server 1.3, so the following directives
prefork
may be migrated directly:
• StartServers
• MinSpareServers
• MaxSpareServers
• MaxClients
• MaxRequestsPerChild
The MPM implements a multi-process, multi-threaded server providing greater scalability.
worker
When using this MPM, requests are handled by threads, conserving system resources and allowing
large numbers of requests to be served efficiently. Although some of the directives accepted by the
MPM are the same as those accepted by the
worker
should not be transfered directly from an Apache HTTP Server 1.3 installation. It is best to instead
use the default values as a guide, then experiment to determine what values work best.
Important
To use the
worker
HTTPD=/usr/sbin/httpd.worker
For more on the topic of MPMs, refer to the following documentation on the Apache Software Foun-
dation's website:
http://httpd.apache.org/docs-2.0/mpm.html
•
10.2.1.3. Dynamic Shared Object (DSO) Support
There are many changes required here, and it is highly recommended that anyone trying to modify an
Apache HTTP Server 1.3 configuration to suit version 2.0 (as opposed to migrating the changes into
the version 2.0 configuration) copy this section from the stock Apache HTTP Server 2.0 configuration
file.
, and
worker perchild
MPM may be made available at a later date.
perchild
MPM, create the file
. Currently only the
prefork
/etc/sysconfig/httpd
Chapter 10. Apache HTTP Server
and
prefork worker
prefork
MPM, the values for those directives
. In the file add the following directive:
MPMs are
MPM. The