From f3ddf96d9b86f47829e2839160f9b4c2ae4cb9f0 Mon Sep 17 00:00:00 2001 From: Jeff Trawick Date: Fri, 18 Jun 2010 17:33:47 +0000 Subject: [PATCH] update doc for connection pools * reduce duplication between initial intro and parameter table * explain that pools are per-process, and limits are not coordinated server-wide * minor clarifications & readability tweaks git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@956059 13f79535-47bb-0310-9956-ffa450edef68 --- docs/manual/mod/mod_proxy.xml | 43 ++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 18 deletions(-) diff --git a/docs/manual/mod/mod_proxy.xml b/docs/manual/mod/mod_proxy.xml index d47722f638..b32d13a8e7 100644 --- a/docs/manual/mod/mod_proxy.xml +++ b/docs/manual/mod/mod_proxy.xml @@ -631,22 +631,29 @@ expressions general ProxyPass directive.

-

As of Apache HTTP Server 2.1, the ability to use pooled connections to a backend - server is available. Using the key=value parameters it is - possible to tune this connection pooling. The default for a Hard - Maximum for the number of connections is the number of threads per - process in the active MPM. In the Prefork MPM, this is always 1, while with - the Worker MPM it is controlled by the - ThreadsPerChild.

- -

Setting min will determine how many connections will always - be open to the backend server. Upto the Soft Maximum or smax - number of connections will be created on demand. Any connections above - smax are subject to a time to live or ttl. Apache httpd - will never create more than the Hard Maximum or max connections - to the backend server.

+

In Apache HTTP Server 2.1 and later, mod_proxy supports pooled + connections to a backend server. Connections created on demand + can be retained in a pool for future use. Limits on the pool size + and other settings can be coded on + the ProxyPass directive + using key=value parameters, described in the table + below.

+ +

Setting min will determine how many connections to + the backend server will be retained after use. Up to the + Soft Maximum, or smax, number of connections will be + created on demand. Any connections above smax are + subject to a time to live, or ttl. Apache httpd will + never create more than the Hard Maximum or, max, + connections to the backend server.

+ +

The pool of connections is maintained per web server child + process, and the min, max, and + and smax settings are not coordinated among all child + processes, except when only one child process is allowed by + configuration or MPM design.

- + Example ProxyPass /example http://backend.example.com smax=5 max=20 ttl=120 retry=300 @@ -656,8 +663,8 @@ expressions Description min 0 - Minimum number of connections that will always - be open to the backend server. + Minimum number of connections to the backend server that + will be retained after use. max 1...n Hard Maximum number of connections that will be @@ -669,7 +676,7 @@ expressions to the backend server. smax max - Upto the Soft Maximum + Up to the Soft Maximum number of connections will be created on demand. Any connections above smax are subject to a time to live or ttl. -- 2.50.1