My initial report stated we were not experiencing any more problems after updating to v1.11.6. However, I confirm now that we are still seeing duplicated tasks. Not as many as before, and none of our annotators have reported any problems like they did before. So my guess is that they don't appear in a loop anymore but only pop up subtly so the annotator doesn't even notice. So it might be that one part of the problem has been fixed, i.e. the "looping tasks" problem. I suspect the remaining part of the problem is related to this thread.
We are using the ner_manual recipe with 4 separate named multi-user sessions (4 dockers, each with 4-5 annotators).
We use "feed_overlap": true since we're building up a reference that relies on multiple annotators annotating the same examples. At some point we tried switching to "exclude_by": "input" to see if that would make any difference, but it didn't. We don't have different questions about the same input yet, so I don't think this parameter is doing anything in that case. We intend on trying out active learning later, so I suppose it will be useful then, right?
Anyway, we upgraded to v1.11.6 on 02.12.2021. Here is a summary of the number of tasks vs number of duplicates for each period after this date. The number of duplicates is the number of duplicated (_session_id, _input_hash) pairs, omitting the first occurrence.
Period: 02.12-03.12
Number of tasks: 159
Number of duplicates: 4
Unique _input_hashes in the set of duplicated tasks: 4
Unique _task_hashes in the set of duplicated tasks: 4
Unique _session_ids in the set of duplicated tasks: 2
Unique multi-user sessions in the set of duplicated tasks: 2
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Period: 03.12-06.12
Number of tasks: 755
Number of duplicates: 15
Unique _input_hashes in the set of duplicated tasks: 15
Unique _task_hashes in the set of duplicated tasks: 15
Unique _session_ids in the set of duplicated tasks: 1
Unique multi-user sessions in the set of duplicated tasks: 1
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Period: 06.12-08.12
Number of tasks: 1945
Number of duplicates: 100
Unique _input_hashes in the set of duplicated tasks: 97
Unique _task_hashes in the set of duplicated tasks: 97
Unique _session_ids in the set of duplicated tasks: 6
Unique multi-user sessions in the set of duplicated tasks: 4
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Period: 08.12-09.12
Number of tasks: 230
Number of duplicates: 0
Unique _input_hashes in the set of duplicated tasks: 0
Unique _task_hashes in the set of duplicated tasks: 0
Unique _session_ids in the set of duplicated tasks: 0
Unique multi-user sessions in the set of duplicated tasks: 0
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Period: 09.12-10.12
Number of tasks: 1083
Number of duplicates: 6
Unique _input_hashes in the set of duplicated tasks: 6
Unique _task_hashes in the set of duplicated tasks: 6
Unique _session_ids in the set of duplicated tasks: 1
Unique multi-user sessions in the set of duplicated tasks: 1
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Period: 10.12-13.12
Number of tasks: 1291
Number of duplicates: 5
Unique _input_hashes in the set of duplicated tasks: 5
Unique _task_hashes in the set of duplicated tasks: 5
Unique _session_ids in the set of duplicated tasks: 3
Unique multi-user sessions in the set of duplicated tasks: 3
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