Drop partition failed

Shyam_Katti

The drop_partition() failed with the following error: "Cannot drop the partition ... concurrent load running .. HINT: Try the operation again". Unfortunately, I do not have the exact error statement available. I could not find anything in the vertica.log file, but the dc_errors table reported the following message approx at the same time: "A mergeout operation (operating on the same set of miniROSs) is already in progress on projection dbadmin.session_resource_usage_nodeX". I am not sure if this is related to the error message I encountered when trying to drop the partition. 2nd issue: We often run into this warning message on Vertica: "event_code_description | Timer Service Task Error event_problem_description | threadShim: A DDL statement interfered with this statement" How can we fix this?

[Deleted User]

Hi Shyam, thanks for reporting your problems here. We'll have someone look into it and help you out. Would you be able to produce the error statement from the drop_partition() failure? This would really help our team diagnose your problems with more accuracy.

Shyam_Katti

Hello Danielle, Thank you for the update. I can try to reproduce it, my only concern being that if the drop partition goes through, we would have to reload the partitions, which is being used right now by other users.

Shyam_Katti

Hello Danielle, Any updates on the issue? Currently, I cannot drop the partitions to recreate the error, but we want to be sure that it won't be a issue once we have this functionality(i.e. dropping partitions and repopulating the database) in production. Thank you!

[Deleted User]

Hi Shyam, It is possible that the mergeout prevents you to drop a partition. I don't know details of your system but you can check if there is any tuple mover activity by doing : select * from tuple_mover_operations where is_executing = 't'; If you have delete vectors on the table that you want to drop partition, the mergeout could consume a lot of time doing reply deletes. Checking the tuple_mover_operations should give you more details. In addition you could check the locks table to see if there is a lock holding the partition too. select * from locks; If both tables, the tuple_mover_operation and the locks table are clean, you should be able to drop the partition. Let me know if this helps or not, Thanks, Eugenia