E_TASK_RUNNING error is returned but ignored by caller.

Deleting"running" task entry is not allowed and error is returned.

But the error is ignored by the callers (
tasksCacheKeyspace.Delete() ,doTask, and "purge"/"abort" session ) this leads to the wrong assumption that the task is deleted.

 

This can happen when analyzeworkload()-Advisor function or updateindexstats()-CREATE/CREATE PRIMARY/BUILD  have prolonged execution times.

 

Repro:

simulate by adding sleep in source https://github.com/couchbase/query/blob/master/scheduler/scheduler.go#L172 

> CREATE INDEX idx1 ON default(a)

> GET http://127.0.0.1:9499/admin/tasks_cache

[
   

{         "class": "update_statistics",         "delay": "1s",         "description": "default:default._default._default(idx100)",         "id": "8a636221-d867-55b3-883b-a7ec83af9efa",         "name": "46453fd4-64c6-4dd0-82ff-72768b509c0e",         "queryContext": "",         "startTime": "2023-12-01T14:01:11.773+05:30",         "state": "running",         "subClass": "create_index",         "submitTime": "2023-12-01T14:01:10.773+05:30"     }

]

 

> DELETE /admin/tasks_cache/46453fd4-64c6-4dd0-82ff-72768b509c0e 

true

 

> DELETE FROM system:tasks_cache WHERE name="46453fd4-64c6-4dd0-82ff-72768b509c0e";

{

    "requestID": "67d8d9e6-13cf-42b3-817a-952a9b5b7eab",

    "signature": null,

    "results": [

    ],

    "status": "success",

    "metrics":

{         "elapsedTime": "1.382542ms",         "executionTime": "1.307167ms",         "resultCount": 0,         "resultSize": 0,         "serviceLoad": 2,         "mutationCount": 1     }

}

 

But the task entry is never actually deleted

>  SELECT * FROM system:tasks_cache;

{

    "requestID": "aba613dd-0243-4ef9-a19b-6a42f14c31e8",

    "signature":

{         "*": "*"     }

,

    "results": [

    {

        "tasks_cache":

{             "class": "update_statistics",             "delay": "1s",             "description": "default:default._default._default(idx100)",             "id": "8a636221-d867-55b3-883b-a7ec83af9efa",             "name": "46453fd4-64c6-4dd0-82ff-72768b509c0e",             "node": "172.16.1.174:9000",             "queryContext": "",             "startTime": "2023-12-01T14:01:11.773+05:30",             "state": "running",             "subClass": "create_index",             "submitTime": "2023-12-01T14:01:10.773+05:30"         }

    }

    ]