IBM WebSphere XS40, Command Reference Manual

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priority
Specifies the priority of a document in the cache. The greater the value, the
higher its priority. Use an integer in the range of 1 through 255. The
default is 128.
ttl Specifies the maximum number of seconds to retain a document in the
cache. Use an integer in the range of 5 through 86400. The default is 900.
nocache
Specifies that documents that conform to the match pattern are not cached.
Guidelines
A Document Cache Policy that defines the following characteristics:
v
Which documents the associated XML manager caches
Cache eligibility is determined by a shell-style match pattern that specifies which
documents (acquired via HTTP) are cached. Candidate documents are evaluated
against the expression. Only documents with a URL that match the expression
are cached.
v
The priority of a document in the cache
When the cache exceeds its maximum size, the assigned priority determines
which documents to delete. Documents with the lowest priority are deleted first.
If multiple documents have the same priority, the least recently-used document
is deleted.
v
The maximum period of time that a document is maintained in the cache
The time-to-live (TTL) or lifetime of the document in the cache. When this time
expires, the document is deleted from the cache.
Policy is set as follows:
v
If the document does not contain a
Data
or
Last-Modified
header, do not cache
the document.
v
If the document contains a
Vary
header, do not cache the document.
v
If the document contains a
Cache-Control
header (HTTP 1.1), cache the
document and use the contents of that field to determine a document shelf-life.
v If the document contains an Expires header (HTTP 1.0), cache the document and
use the contents of that field to determine a document shelf-life.
v
If the document contains a
Last-Modified
header, cache the document and use
the contents of that field (in conjunction with the
Data
header) to heuristically
determine a document shelf-life (not to exceed 8 hours).
You can specify multiple document cache policies. Candidate documents are
evaluated against each policy in order and immediately cached in the event of a
match. Consequently, the order of policies is important when using the
nocache
keyword.
Use the no policy with a match pattern to delete specific cache policies. Use no
policy without arguments to delete all cache policies. These commands delete the
policies, not the documents in the cache.
Related Commands
clear , size
Examples
v
Caches all XML schemas with the default priority and TTL.
Chapter 17. Document Cache configuration mode
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