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Apache Module mod_disk_cache

Description:	Content cache storage manager keyed to URIs
Status:	Experimental
Module Identifier:	disk_cache_module
Source File:	mod_disk_cache.c

Summary

This module is experimental. Documentation is still under development...

mod_disk_cache implements a disk based storage manager. It is primarily of use in conjunction with mod_proxy.

Content is stored in and retrieved from the cache using URI based keys. Content with access protection is not cached.

Note:

mod_disk_cache requires the services of mod_cache.

Directives

CacheDirLength Directive

Description:	The number of characters in subdirectory names
Syntax:	`CacheDirLength length`
Default:	`CacheDirLength 2`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

The CacheDirLength directive sets the number of characters for each subdirectory name in the cache hierarchy.

The result of CacheDirLevels* CacheDirLength must not be higher than 20.

CacheDirLength 4

CacheDirLevels Directive

Description:	The number of levels of subdirectories in the cache.
Syntax:	`CacheDirLevels levels`
Default:	`CacheDirLevels 3`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

The CacheDirLevels directive sets the number of subdirectory levels in the cache. Cached data will be saved this many directory levels below the CacheRoot directory.

The result of CacheDirLevels* CacheDirLength must not be higher than 20.

CacheDirLevels 5

CacheExpiryCheck Directive

Description:	Indicates if the cache observes Expires dates when seeking files
Syntax:	`CacheExpiryCheck On\|Off`
Default:	`CacheExpiryCheck On`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

More detail will be added here, when the function is implemented.

CacheExpiryCheck Off

The CacheExpiryCheck directive is currently not implemented.

CacheGcClean Directive

Description:	The time to retain unchanged cached files that match a URL
Syntax:	`CacheGcClean hours url-string`
Default:	`CacheGcClean ?`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

More detail will be added here, when the function is implemented.

CacheGcClean 12 /daily_scripts

The CacheGcClean directive is currently not implemented.

CacheGcDaily Directive

Description:	The recurring time each day for garbage collection to be run. (24 hour clock)
Syntax:	`CacheGcDaily time`
Default:	`CacheGcDaily ?`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

More detail will be added here, when the function is implemented.

CacheGcDaily 23:59

The CacheGcDaily directive is currently not implemented.

CacheGcInterval Directive

Description:	The interval between garbage collection attempts.
Syntax:	`CacheGcInterval hours`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

The CacheGcInterval directive specifies the number of hours to wait between attempts to free up disk space.

More detail will be added here, when the function is implemented.

CacheGcInterval 24

The CacheGcInterval directive is currently not implemented.

CacheGcMemUsage Directive

Description:	The maximum kilobytes of memory used for garbage collection
Syntax:	`CacheGcMemUsage KBytes`
Default:	`CacheGcMemUsage ?`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

More detail will be added here, when the function is implemented.

CacheGcMemUsage 16

The CacheGcMemUsage directive is currently not implemented.

CacheGcUnused Directive

Description:	The time to retain unreferenced cached files that match a URL.
Syntax:	`CacheGcUnused hours url-string`
Default:	`CacheGcUnused ?`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

More detail will be added here, when the function is implemented.

CacheGcUnused 12 /local_images

The CacheGcUnused directive is currently not implemented.

CacheMaxFileSize Directive

Description:	The maximum size (in bytes) of a document to be placed in the cache
Syntax:	`CacheMaxFileSize bytes`
Default:	`CacheMaxFileSize 1000000`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

The CacheMaxFileSize directive sets the maximum size, in bytes, for a document to be considered for storage in the cache.

CacheMaxFileSize 64000

CacheMinFileSize Directive

Description:	The minimum size (in bytes) of a document to be placed in the cache
Syntax:	`CacheMinFileSize bytes`
Default:	`CacheMinFileSize 1`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

The CacheMinFileSize directive sets the minimum size, in bytes, for a document to be considered for storage in the cache.

CacheMinFileSize 64

CacheRoot Directive

Description:	The directory root under which cache files are stored
Syntax:	`CacheRoot directory`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

The CacheRoot directive defines the name of the directory on the disk to contain cache files. If the mod_disk_cache module has been loaded or compiled in to the Apache server, this directive must be defined. Failing to provide a value for CacheRoot will result in a configuration file processing error. The CacheDirLevels and CacheDirLength directives define the structure of the directories under the specified root directory.

CacheRoot c:/cacheroot

CacheSize Directive

Description:	The maximum amount of disk space that will be used by the cache in KBytes
Syntax:	`CacheSize KBytes`
Default:	`CacheSize 1000000`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

The CacheSize directive sets the desired disk space usage of the cache, in KBytes (1024-byte units). This directive does not put a hard limit on the size of the cache. The garbage collector will delete files until the usage is at or below the settings. Always use a value that is lower than the available disk space.

CacheSize 5000000

CacheTimeMargin Directive

Description:	The minimum time margin to cache a document
Syntax:	`CacheTimeMargin ?`
Default:	`CacheTimeMargin ?`
Context:	server config, virtual host
Status:	Experimental
Module:	mod_disk_cache

More detail will be added here, when the function is implemented.

CacheTimeMargin X

The CacheTimeMargin directive is currently not implemented.