MongoDB C# Driver 'Cursor not found'

Question

I have quite an intensive operation that has a MongoCursor run in a loop for a few hours (on a vb.net app running via the c# driver. I'm not too sure what causes it but I run into an exception after a while

Cursor not found

This could be because of a cursor timeout, perhaps? Is there a way I can stop it happening? If its a timeout issue how do I place a longer timeout?

score 17 · Accepted Answer · answered Dec 27 '12 at 15:09

17

You can disable the cursor's timeout in the C# driver by calling:

cursor.SetFlags(QueryFlags.NoCursorTimeout);

Otherwise it will be closed after 10 minutes of inactivity.

Reference

answered Dec 27 '12 at 15:09

JohnnyHK

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If you don't exhaust the cursor to the last element, this will cause a memory leak in mongo. – Nashenas Nov 30 '15 at 18:19
You can also change the batch size (as per http://stackoverflow.com/a/24200795/420867 - it's a python question but the same should be possible with the C# mongo driver) – drevicko Feb 07 '16 at 17:31

score 2 · Answer 2 · answered Sep 02 '14 at 02:45

Further clarifying JohnnyHK's answer, this is the syntax:

MongoCursor<BsonDocument> cursor = myCollection
                                   .Find(query)
                                   .SetSortOrder(SortBy.Ascending("TrackingNumber"))
                                   .SetFlags(QueryFlags.NoCursorTimeout);

score 1 · Answer 3 · answered Jun 12 '17 at 09:09

1

I'm using MongoDB.Driver version 2.4.4 and IFindFluent is not containing SetFlags method. using this instead:

cursor.Options.NoCursorTimeout = true;

answered Jun 12 '17 at 09:09

thirdDeveloper

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What would happen if NoCursorTimeout is set to true and u have exhausted the cursor ? Would there be any memory leak or performance issues? – suresh rajput Mar 30 '21 at 05:07

MongoDB C# Driver 'Cursor not found'

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