I’m running a sharded cluster and I recently upgraded mongo from 3.0 to 4.2. Some programs that run previously without errors now raise CursorNotFound error in loops like
for rec in aggregation_query: process(rec)
where process can be quite time consuming and aggregation_query can return > 10000 values…
Errors come around 65mn from the beginning of the job (so much lower than the cursor timeout parameter, see below)
I don’t use explicit sessions
DB parameters cursorTimeoutMillis and localLogicalSessionTimeoutMinutes have already be “ugraded” to the equivalent of 2 hours (7200000 and 120 respectively).
How can I get more information (which systemLog component should I put to a debug level) ?
Any idea of how to solve that ?
Messages are like
CursorNotFound: Cursor not found (namespace: 'my_db.my_collection', id: 5454438319793971081)
In which log (mongod or mongos) can I find this id ?
Context is : mongoDB 4.2.3, pymongo 3.10.1