New in version 2.6.
maxTimeMS( <time limit> )
Specifies a cumulative time limit in milliseconds for processing operations on a cursor.
maxTimeMS()method has the following parameter:
Parameter Type Description
integer Specifies a cumulative time limit in milliseconds for processing operations on the cursor.
MongoDB targets operations for termination if the associated cursor exceeds its allotted time limit. MongoDB terminates operations that exceed their allotted time limit using the same mechanism as
db.killOp(). MongoDB only terminates an operation at one of its designated interrupt points.
MongoDB does not count network latency towards a cursor’s time limit.
Queries that generate multiple batches of results continue to return batches until the cursor exceeds its allotted time limit.
Starting in MongoDB 3.6, MongoDB drivers and the
mongo shell associate all operations with a server session, with the exception of unacknowledged write operations. For operations not explicitly associated with a session (i.e. using
Mongo.startSession()), MongoDB drivers and the
mongo shell creates an implicit session and associates it with the operation.
If a session is idle for longer than 30 minutes, the MongoDB server marks that session as expired and may close it at any time. When the MongoDB server closes the session, it also kills any in-progress operations and open cursors associated with the session. This includes cursors configured with
noCursorTimeout or a
maxTimeMS greater than 30 minutes.
For example, consider a
find() operation with the
maxTimeMS configured for a timeout of 31 minutes. The server returns a cursor along with a batch of documents defined by the
cursor.batchSize() of the
find(). The session refreshes each time the application requests a new batch of documents from the server. However, if the application takes longer than 30 minutes to process the current batch of documents, the session is marked as expired and closed. When the server closes the session, it also kills the cursor despite the cursor being configured with
maxTimeMS greater than 30 minutes. When the application requests the next batch of documents, the server returns an error.
For operations that return a cursor, if the cursor may be idle for longer than 30 minutes, issue the operation within an explicit session using
Session.startSession() and periodically refresh the session using the
refreshSessions command. For example:
In the example operation, the
db.collection.find() method is associated with an explicit session. The cursor is configured with
cursor.maxTimeMS() to keep the cursor open for at least 31 minutes. The
while loop includes a block that uses
refreshSessions to refresh the session every 5 minutes. Since the session will never exceed the 30 minute idle timeout, the cursor can remain open up to the configured
For MongoDB drivers, defer to the driver documentation for instructions and syntax for creating sessions.