From ba439e10fa6445ebc51dddb88d2db3c2b8a496ff Mon Sep 17 00:00:00 2001 From: Andre Malo Date: Thu, 14 Nov 2002 04:10:56 +0000 Subject: [PATCH] update transformation git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@97512 13f79535-47bb-0310-9956-ffa450edef68 --- docs/manual/mod/mod_file_cache.html.en | 178 ++++++++++++------------- docs/manual/mod/quickreference.html.en | 5 +- 2 files changed, 90 insertions(+), 93 deletions(-) diff --git a/docs/manual/mod/mod_file_cache.html.en b/docs/manual/mod/mod_file_cache.html.en index 23a44ab00e..006d01e3fd 100644 --- a/docs/manual/mod/mod_file_cache.html.en +++ b/docs/manual/mod/mod_file_cache.html.en @@ -10,20 +10,20 @@ file_cache_moduleSource File: mod_file_cache.c

Summary

-
-This module should be used with care. You can easily - create a broken site using mod_file_cache, so read this - document carefully. -
+
+ This module should be used with care. You can easily create a broken + site using mod_file_cache, so read this document + carefully. +

Caching frequently requested files that change very infrequently is a technique for reducing server load. - mod_file_cache provides two techniques for caching frequently - requested static files. Through configuration - directives, you can direct mod_file_cache to either open then - mmap()a file, or to pre-open a file and save the file's open - file handle. Both techniques reduce server load when - processing requests for these files by doing part of the work + mod_file_cache provides two techniques for caching + frequently requested static files. Through configuration + directives, you can direct mod_file_cache to either + open then mmap() a file, or to pre-open a file and save + the file's open file handle. Both techniques reduce server + load when processing requests for these files by doing part of the work (specifically, the file I/O) for serving the file when the server is started rather than during each request.

@@ -33,14 +33,13 @@ This module should be used with care. You can easily the Apache core content handler.

This module is an extension of and borrows heavily from the - mod_mmap_static module in Apache 1.3.

+ mod_mmap_static module in Apache 1.3.

Directives

Topics

top

Using mod_file_cache

+

Topics

top

Using mod_file_cache

mod_file_cache caches a list of statically - configured files via MMapFile or CacheFile directives in the - main server configuration.

+ configured files via MMapFile or CacheFile directives in the main server configuration.

Not all platforms support both directives. For example, Apache on Windows does not currently support the MMapStatic directive, while @@ -51,70 +50,69 @@ This module should be used with care. You can easily that support both directives, you should experiment with both to see which works best for you.

-

MmapFile Directive

- -

The MmapFile - directive of mod_file_cache maps a list of - statically configured files into memory through the system call - mmap(). This system call is available on most modern - Unix derivates, but not on all. There are sometimes - system-specific limits on the size and number of files that can be - mmap()d, experimentation is probably the easiest way to find - out.

- -

This mmap()ing is done once at server start or restart, - only. So whenever one of the mapped files changes on the - filesystem you have to restart the server (see the Stopping and Restarting - documentation). To reiterate that point: if the files are - modified in place without restarting the server you - may end up serving requests that are completely bogus. You - should update files by unlinking the old copy and putting a new - copy in place. Most tools such as rdist and - mv do this. The reason why this modules doesn't - take care of changes to the files is that this check would need - an extra stat() every time which is a waste and - against the intent of I/O reduction.

- - -

CacheFile Directive

- -

The CacheFile - directive of mod_file_cache opens an active - handle or file descriptor to the file (or files) - listed in the configuration directive and places these open file - handles in the cache. When the file is requested, the server - retrieves the handle from the cache and passes it to the - sendfile() (or TransmitFile() on Windows), socket API.

- -

Insert more details about sendfile API...

- -

This file handle caching is done once at server start or - restart, only. So whenever one of the cached files changes on - the filesystem you have to restart the server (see the - Stopping and Restarting - documentation). To reiterate that point: if the files are - modified in place without restarting the server you - may end up serving requests that are completely bogus. You - should update files by unlinking the old copy and putting a new - copy in place. Most tools such as rdist and - mv do this.

- - -

Note

Don't bother asking for a for a - directive which recursively caches all the files in a - directory. Try this instead... See the - Include directive, and consider - this command: -

- find /www/htdocs -type f -print \
- | sed -e 's/.*/mmapfile &/' > /www/conf/mmap.conf -

-
- +

MMapFile Directive

+ +

The MMapFile + directive of mod_file_cache maps a list of + statically configured files into memory through the system call + mmap(). This system call is available on most modern + Unix derivates, but not on all. There are sometimes system-specific + limits on the size and number of files that can be + mmap()ed, experimentation is probably the easiest way + to find out.

+ +

This mmap()ing is done once at server start or + restart, only. So whenever one of the mapped files changes on the + filesystem you have to restart the server (see the Stopping and Restarting documentation). + To reiterate that point: if the files are modified in place + without restarting the server you may end up serving requests that + are completely bogus. You should update files by unlinking the old + copy and putting a new copy in place. Most tools such as + rdist and mv do this. The reason why this + modules doesn't take care of changes to the files is that this check + would need an extra stat() every time which is a waste + and against the intent of I/O reduction.

+ + +

CacheFile Directive

+ +

The CacheFile + directive of mod_file_cache opens an active + handle or file descriptor to the file (or files) + listed in the configuration directive and places these open file + handles in the cache. When the file is requested, the server + retrieves the handle from the cache and passes it to the + sendfile() (or TransmitFile() on Windows), + socket API.

+ + + +

This file handle caching is done once at server start or + restart, only. So whenever one of the cached files changes on + the filesystem you have to restart the server (see the + Stopping and Restarting + documentation). To reiterate that point: if the files are + modified in place without restarting the server you + may end up serving requests that are completely bogus. You + should update files by unlinking the old copy and putting a new + copy in place. Most tools such as rdist and + mv do this.

+ + +

Note

+

Don't bother asking for a for a directive which recursively + caches all the files in a directory. Try this instead... See the + Include directive, and consider + this command:

+ +

+ find /www/htdocs -type f -print \
+ | sed -e 's/.*/mmapfile &/' > /www/conf/mmap.conf +

+
top

CacheFile Directive

Description: -
Syntax: - CacheFile - file-path [file-path] ...
Context: + Cache a list of file handles at startup time
Syntax: + CacheFile file-path [file-path] ...
Context: server config
Status: Experimental
Module: mod_file_cache
@@ -125,7 +123,7 @@ This module should be used with care. You can easily shutdown. When the files have changed on the filesystem, the server should be restarted to to re-cache them.

-

Be careful with the file-path arguments: They have +

Be careful with the file-path arguments: They have to literally match the filesystem path Apache's URL-to-filename translation handlers create. We cannot compare inodes or other stuff to match paths through symbolic links etc. @@ -134,12 +132,12 @@ This module should be used with care. You can easily with filenames rewritten by mod_alias or mod_rewrite.

-

Example

- CacheFile /usr/local/apache/htdocs/index.html -

+

Example

+ CacheFile /usr/local/apache/htdocs/index.html +

top

MMapFile Directive

Description: -
Syntax: - MMapFile file-path [file-path] ...
Context: + Map a list of files into memory at startup time
Syntax: + MMapFile file-path [file-path] ...
Context: server config
Status: Experimental
Module: mod_file_cache
@@ -147,10 +145,10 @@ This module should be used with care. You can easily (given as whitespace separated arguments) into memory at server startup time. They are automatically unmapped on a server shutdown. When the files have changed on the filesystem at - least a HUP or USR1 signal should be send to the server to - re-mmap them.

+ least a HUP or USR1 signal should be send to + the server to re-mmap() them.

-

Be careful with the file-path arguments: They have +

Be careful with the file-path arguments: They have to literally match the filesystem path Apache's URL-to-filename translation handlers create. We cannot compare inodes or other stuff to match paths through symbolic links etc. @@ -159,7 +157,7 @@ This module should be used with care. You can easily with filenames rewritten by mod_alias or mod_rewrite.

-

Example

- MMapFile /usr/local/apache/htdocs/index.html -

+

Example

+ MMapFile /usr/local/apache/htdocs/index.html +

\ No newline at end of file diff --git a/docs/manual/mod/quickreference.html.en b/docs/manual/mod/quickreference.html.en index a80bcb2a2b..8761d613be 100644 --- a/docs/manual/mod/quickreference.html.en +++ b/docs/manual/mod/quickreference.html.en @@ -174,8 +174,7 @@ cache. manager CacheExpiryCheck On|Off On svXIndicates if the cache observes Expires dates when seeking files -CacheFile - file-path [file-path] ...sX- +CacheFile file-path [file-path] ...sXCache a list of file handles at startup time CacheForceCompletion Percentage 60 svXPercentage of document served, after which the server will complete caching the file even if the request is cancelled. CacheGcClean hours url-string ? svXThe time to retain unchanged cached files that match a @@ -403,7 +402,7 @@ using the specified magic file MinSpareServers number 5 sMMinimum number of idle child server processes MinSpareThreads numbersMMinimum number of idle threads available to handle request spikes -MMapFile file-path [file-path] ...sX- +MMapFile file-path [file-path] ...sXMap a list of files into memory at startup time ModMimeUsePathInfo On|OffdBTells mod_mime to treat path_info components as part of the filename MultiviewsMatch [NegotiatedOnly] [Handlers] [Filters] [Any]svdhBThe types of files that will be included when -- 2.40.0