DOC: cache: Add new caching limitation information

Responses that do not have an explicit expiration time or a validator
will not be cached anymore.

Must be backported if cc9bf2e ("MEDIUM: cache: Change caching
conditions") is backported.

diff --git a/doc/configuration.txt b/doc/configuration.txt
index ee93b396932690f78174819e870b621f685f6fbb..ccc116e104a1a0f0705f29cb85e6ce8981b930b9 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -14300,6 +14300,9 @@ The cache won't store and won't deliver objects in these cases:
 - If the response contains a Vary header
 - If the Content-Length + the headers size is greater than "max-object-size"
 - If the response is not cacheable
+- If the response does not have an explicit expiration time (s-maxage or max-age
+  Cache-Control directives or Expires header) or a validator (ETag or Last-Modified
+  headers)
 
 - If the request is not a GET
 - If the HTTP version of the request is smaller than 1.1