You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@trafficserver.apache.org by "midchildan (via GitHub)" <gi...@apache.org> on 2023/05/07 17:10:32 UTC
[GitHub] [trafficserver] midchildan opened a new issue, #9687: TS_MILESTONE_CACHE_OPEN_READ_END is unavailable in TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK after 9.1.x
midchildan opened a new issue, #9687:
URL: https://github.com/apache/trafficserver/issues/9687
Prior to 9.1.x, HTTP transactions reached `TS_MILESTONE_CACHE_OPEN_READ_END` before `TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK`. However, after 9.1.x, the order was reversed. This has affected one of our plugins because it was failing to obtain the correct timestamp of the completion of cache reads in a timely manner.
The exact change that caused this was made in #8168. Previously, `TS_MILESTONE_CACHE_OPEN_READ_END` was placed at the beginning of `HttpSM::state_cache_open_read`. After the change, it was moved to the end of the same function. The problem is that `state_cache_open_read` now calls into the HTTP state machine before it reaches the milestone [1] [2]. Once the state machine is invoked, the HTTP transaction will progress further and won't return until it triggers an asynchronous operation along the way.
The new timing for `TS_MILESTONE_CACHE_OPEN_READ_END` varies depending on the result of the cache lookup. When it misses, the milestone will be reached as ATS attempts to connect to the origin server. When it's a hit, the milestone will be delayed even further, past the point where it prepares to send a response back to the client in `TS_HTTTP_SEND_RESPONSE_HDR_HOOK`.
Is it okay to revert to the previous behavior by moving the milestone back to its original location? Or were there any problems with it?
[1]: https://github.com/apache/trafficserver/blob/4cf91f8acd7290e960edefc6b5f87d8a50d2271f/proxy/http/HttpSM.cc#L2746
[2]: https://github.com/apache/trafficserver/blob/4cf91f8acd7290e960edefc6b5f87d8a50d2271f/proxy/http/HttpSM.cc#L2766
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
Re: [I] TS_MILESTONE_CACHE_OPEN_READ_END is unavailable in TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK after 9.1.x [trafficserver]
Posted by "github-actions[bot] (via GitHub)" <gi...@apache.org>.
github-actions[bot] commented on issue #9687:
URL: https://github.com/apache/trafficserver/issues/9687#issuecomment-2099578745
This issue has been automatically marked as stale because it has not had recent activity. Marking it stale to flag it for further consideration by the community.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
Re: [I] TS_MILESTONE_CACHE_OPEN_READ_END is unavailable in TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK after 9.1.x [trafficserver]
Posted by "bryancall (via GitHub)" <gi...@apache.org>.
bryancall commented on issue #9687:
URL: https://github.com/apache/trafficserver/issues/9687#issuecomment-4828018814
This is fixed. TS_MILESTONE_CACHE_OPEN_READ_END is now stamped in the terminal cache-open-read handling paths of HttpSM::state_cache_open_read before the state machine advances into cache serving or origin connect, so the milestone is available in time for TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK again. On current master, the hit path sets it before call_transact_and_set_next_state(HandleCacheOpenRead) and the miss path sets it before setup_cache_lookup_complete_api(). The fix shipped in https://github.com/apache/trafficserver/pull/13325, first released in 10.1.3. Closing as resolved.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org
Re: [I] TS_MILESTONE_CACHE_OPEN_READ_END is unavailable in TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK after 9.1.x [trafficserver]
Posted by "bryancall (via GitHub)" <gi...@apache.org>.
bryancall closed issue #9687: TS_MILESTONE_CACHE_OPEN_READ_END is unavailable in TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK after 9.1.x
URL: https://github.com/apache/trafficserver/issues/9687
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org
For queries about this service, please contact Infrastructure at:
users@infra.apache.org