This work aims at supporting strong cache validation and Vary matches
of objects using the ETag header.
- The ETag header
- Description of what the ETag header is
- How to implement ETag in Squid
- Store format
- Store format used to support ETag indexing of varying objects
- Cache hit processing
- How to find and process cache hits
- Tests & verifications
- Things to test and verify
- Fix ETag processing of large indexes
- Fix processing of ETag on aborted requests (http->entry == NULL)
- Port to new store API
- Cache validations of tagged objects (ETag) not carrying a "Last-Modified" timestamp.
- Optimize expired entity matches after If-None-Match to count the If-None-Match as a cache validation.
- Optimize ETag index updates to not touch the disk store if there is no change.
- 2006-06-30 Many bugfixes in 2.6
- Many ETag related bugs have been fixed in 2.6 after the merge.
- 2006-06-07 broken_vary_encoding workaround in 2.6
- Workaround for many broken Content-Encoding transforming servers (Apache mod_deflate, mod_gzip, quite likely others) not updating ETag proper.
- 2006-05-25 Merged into 2.6
- ETag support has been merged into Squid-2.6.
- 2002-08-16 index fixes
- Various Vary/ETag index fixes
- 2002-08-15 memory corruption bugfix
- In some conditions the ETag swapin buffer wasn't freed correctly, possibly causing memory corruption.
- 2002-04-02 memorybuf bugfixes
- Some bugfixes in the inherited memorybuf branch
- 2002-02-23 Bugfix: Large ETag indexes
- Fix handling of large ETag indexes
- 2002-02-13 Bugfix: ETag index processing
- Various bugfixes to ETag index processing
- 2001-06-12 Bugfix: If-Range using LMT
- If-Range using LMT timestamps could falsely match is the indicated LMT was newer than a cached copy.
- 2001-06-01 Bugfix: If-None-Match on cache validations
- If-None-Match now also supported on cache validations. Returns the servers
304 reply if the ETag (of the reply) matches.
- 2001-06-01 More bugfixes for varying objects without ETag
- Cache hits on varying objects without ETag also crashed Squid
- 2001-06-01 Small memory leak on Vary misses
- Fixed a memory leak on Vary misses where the ETag index was updated
- 2001-05-01 Debug log levels
- Debug log levels have adjusted to not log anything
- 2001-06-01 Bugfix for varying objects without a ETag
- Crashed if a varying object was received without a ETag
- 2001-05-31 Squid-2.4 port
- The etag changes have been ported to Squid-2.4 patched for Vary support
- 2001-05-31 If-None-Match and If-Match client side
- If-Match and If-None-Match is now supported in client side requests. If the cached etag does not match If-Match then a the request is processed as a cache miss. If it does match If-None-Match then it is processed as a IMS HIT (304 reply).
- 2001-05-31 Many small bugs hunted down
- No longer fails basic tests or leaks huge amounts of memory. There is one known memory leak on cache validations, but it looks like this might be a generic problem not actually caused by the ETag changes..
- 2001-05-30 If-None-Match etag queries
- On cache misses for varying object If-None-Match is now used to query the origin server which (if any) of the caced entities matches the request.
- 2001-05-30 If-None-Match cache validation
- If-None-Match is now used on cache validations, using the entity tag of the exact object being validated. This ensures that even sub-second updates are detected properly, and cache validation is now less time sensitive.
- 2001-05-29 Entity tag cache hits
- The entity-tag/variant index is now consulted on cache hits, making the implementation at least equal to "basic vary" but with a more compressed store (identical variants are only stored once)
- 2001-05-28 Entity tag and variant index
- A index of known entity tags and variants are being kept for varying objects. This index is kept within the internal "vary" marker object.
- 2001-05-25 Issues identified
- ETag implementation issues identified
- 2001-05-23 ETag documentation
- Most ETag relevant documentation collected
$Id: index.html,v 1.25 2006/07/01 15:00:28 hno Exp $