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Richard Eckart de Castilho commented on UIMA-6048: -------------------------------------------------- DUCC has been retired. > UIMA-DUCC: simplify pullservice protocol > ---------------------------------------- > > Key: UIMA-6048 > URL: https://issues.apache.org/jira/browse/UIMA-6048 > Project: UIMA > Issue Type: Improvement > Components: DUCC > Reporter: Jaroslaw Cwiklik > Assignee: Jaroslaw Cwiklik > Priority: Major > Fix For: future-DUCC > > > Currently the pullservice uses 3 way protocol when communicating with a > client (like JD). Its GET, ACK, and END. Each requires a round trip from a > pullservice to the client and back. > It would be more efficient to remove the ACK, call GET once (to get initial > task) and just keep calling END which would do two things: > Convey end of task (success or failure) > Return new task to process > The ACK was a carry over from the time when JMS (ActiveMQ) was used as > transport and it occasionally was loosing tasks. Its main function was to > indicate which service (and thread) was processing the task. HTTP seems more > robust and the ACK is no longer necessary. > To support the new protocol, JD needs refactoring to stop relying on ACK and > also to fetch a new task (or null) in response to END. > > > -- This message was sent by Atlassian Jira (v8.20.10#820010)