Apache HTTP Server Version 2.4
Apache HTTP Server Version 2.4
| Description: | Disk based storage module for the HTTP caching filter. |
|---|---|
| Status: | Extension |
| Module Identifier: | cache_disk_module |
| Source File: | mod_cache_disk.c |
mod_cache_disk implements a disk based storage
manager for mod_cache.
The headers and bodies of cached responses are stored separately on disk, in a directory structure derived from the md5 hash of the cached URL.
Multiple content negotiated responses can be stored concurrently, however the caching of partial content is not yet supported by this module.
Atomic cache updates to both header and body files are achieved without the need for locking by storing the device and inode numbers of the body file within the header file. This has the side effect that cache entries manually moved into the cache will be ignored.
The htcacheclean tool is provided to list cached
URLs, remove cached URLs, or to maintain the size of the disk cache
within size and/or inode limits. The tool can be run on demand, or
can be daemonized to offer continuous monitoring of directory sizes.
mod_cache_disk requires the services of
mod_cache, which must be
loaded before mod_cache_disk.
mod_cache_disk uses the sendfile feature to
serve files from the cache when supported by the platform, and
when enabled with EnableSendfile.
However, per-directory and .htaccess configuration of
EnableSendfile are ignored by
mod_cache_disk as the corresponding settings are not
available to the module when a request is being served from the
cache.
