mod_disk_cache
Content cache storage manager keyed to URIs
Experimental
mod_disk_cache.c
disk_cache_module

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.

CacheRoot
The directory root under which cache files are stored
CacheRoot directory
server config
virtual host

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
The maximum amount of disk space that will be used by the cache in KBytes
CacheSize KBytes
CacheSize 1000000
server config
virtual host

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
CacheGcInterval
The interval between garbage collection attempts.
CacheGcInterval hours
server config
virtual host

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.

CacheDirLevels
The number of levels of subdirectories in the cache.
CacheDirLevels levels
CacheDirLevels 3
server config
virtual host

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
CacheDirLength
The number of characters in subdirectory names
CacheDirLength length
CacheDirLength 2
server config
virtual host

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
CacheExpiryCheck
Indicates if the cache observes Expires dates when seeking files
CacheExpiryCheck On|Off
CacheExpiryCheck On
server config
virtual host

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

CacheExpiryCheck Off

The CacheExpiryCheck directive is currently not implemented.

CacheMinFileSize
The minimum size (in bytes) of a document to be placed in the cache
CacheMinFileSize bytes
CacheMinFileSize 1
server config
virtual host

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

CacheMinFileSize 64
CacheMaxFileSize
The maximum size (in bytes) of a document to be placed in the cache
CacheMaxFileSize bytes
CacheMaxFileSize 1000000
server config
virtual host

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

CacheMaxFileSize 64000
CacheTimeMargin
The minimum time margin to cache a document
CacheTimeMargin ?
CacheTimeMargin ?
server config
virtual host

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

CacheTimeMargin X

The CacheTimeMargin directive is currently not implemented.

CacheGcDaily
The recurring time each day for garbage collection to be run. (24 hour clock)
CacheGcDaily time
CacheGcDaily ?
server config
virtual host

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

CacheGcDaily 23:59

The CacheGcDaily directive is currently not implemented.

CacheGcUnused
The time to retain unreferenced cached files that match a URL.
CacheGcUnused hours url-string
CacheGcUnused ?
server config
virtual host

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

CacheGcUnused 12 /local_images

The CacheGcUnused directive is currently not implemented.

CacheGcClean
The time to retain unchanged cached files that match a URL
CacheGcClean hours url-string
CacheGcClean ?
server config
virtual host

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

CacheGcClean 12 /daily_scripts

The CacheGcClean directive is currently not implemented.

CacheGcMemUsage
The maximum kilobytes of memory used for garbage collection
CacheGcMemUsage KBytes
CacheGcMemUsage ?
server config
virtual host

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

CacheGcMemUsage 16

The CacheGcMemUsage directive is currently not implemented.