10.5.63. Cache Directives

A number of commented cache directives are supplied by the default Apache HTTP Server configuration file. In most cases, uncommenting these lines by removing the hash mark (#) from the beginning of the line is sufficient. The following, however, is a list of some of the more important cache-related directives.
  • CacheEnable — Specifies whether the cache is a disk, memory, or file descriptor cache. By default CacheEnable configures a disk cache for URLs at or below /.
  • CacheRoot — Specifies the name of the directory containing cached files. The default CacheRoot is the /var/httpd/proxy/ directory.
  • CacheSize — Specifies how much space the cache can use in kilobytes. The default CacheSize is 5 KB.
The following is a list of some of the other common cache-related directives.
  • CacheMaxExpire — Specifies how long HTML documents are retained (without a reload from the originating Web server) in the cache. The default is 24 hours (86400 seconds).
  • CacheLastModifiedFactor — Specifies the creation of an expiry (expiration) date for a document which did not come from its originating server with its own expiry set. The default CacheLastModifiedFactor is set to 0.1, meaning that the expiry date for such documents equals one-tenth of the amount of time since the document was last modified.
  • CacheDefaultExpire — Specifies the expiry time in hours for a document that was received using a protocol that does not support expiry times. The default is set to 1 hour (3600 seconds).
  • NoProxy — Specifies a space-separated list of subnets, IP addresses, domains, or hosts whose content is not cached. This setting is most useful for Intranet sites.