ramandumcs edited a comment on issue #5353: AIRFLOW-4586 There is no need to 
check explicitly for queued dependen…
URL: https://github.com/apache/airflow/pull/5353#issuecomment-498317615
 
 
   We are observing that occasionally Tasks get stuck in queued state and never 
get executed by Airflow. On debugging it we found that one of the queued 
dependency was not met due to which task did not move from queued to running 
state. So task remained in queued state. (are_dependencies_met function 
returned false for QUEUE_DEPS inside _check_and_change_state_before_execution).
   
   By looking into scheduler code it seems that scheduler does not reschedule 
the queued state tasks due to which task never got added to executor queue 
again and remained stuck in queued state. if RUN_DEPS are not met, task is 
moved from queued to None state(which gets picked by scheduler for 
rescheduling) but task remains in queued state ifQUEUE_DEPS are not met. So 
task should be moved to None/up_for_retry state  if QUEUE_DEPS are not met.

----------------------------------------------------------------
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

Reply via email to