bdoyle0182 commented on issue #4842: Race Condition with Activation Completion Ack Back to Controller and Activation Write to Couchdb? URL: https://github.com/apache/openwhisk/issues/4842#issuecomment-592102853 > This is by design - it's possible for an activation record to be "lost" in that it may not be recorded in the activation store but its results are externally observable (either via request/response, a continuation or a sequence). This is an area where the semantics and implementation could be improved. > > The design partly stems from the at most once activation model, and only recording the activation metadata once after completion. The active ack is the fast pass and is sent ahead of log collection. The activation metadata waits for the logs to be drained (which can delay the write back noticeably). Thanks for the answer, I figured this was probably the case. Our use case for openwhisk is entirely non-blocking activations so we rely on getting the result from the activation store. Well we hit the quark controller http endpoint for the activation with the activationId which gets it from couchdb (assuming it's not cached). When you say request/response, do you mean it's results are guaranteed externally observable for blocking activations? In the event that the activation record is lost and all of the controllers are restarted, there's never a way to get information on that activation again right? Also yes, I did see the elasticsearch pull request for activations. We are actually interested in moving activations off couchdb, but not necessarily to elasticsearch. It's great to know that swapping out activation stores is now going to be supported though. What is your opinion on us implementing an object store (i.e. s3) `ActivationStore` for activations? The other db we would be considering moving activations to is mongo. Curious on your thoughts
---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
