Is the connection pool configured by mongodb full? Daniel Stojanov <m...@danielstojanov.com> 于2020年10月26日周一 上午10:28写道：
> Hi, > > > I receive an error message from the MongoDB server if there are too many > Spark applications trying to access the database at the same time (about > 3 or 4), "Cannot open a new cursor since too many cursors are already > opened." I am not too sure of how to remedy this. I am not sure how the > plugin behaves when it's pulling data. > > It appears that a given running application will open many connections > to the database. The total number of cursors in the database's setting > is many more than the number of read operations occurring in Spark. > > > Does the plugin keep a connection/cursor open to the database even after > it has pulled out the data into a dataframe? > > Why are there so many open cursors for a single read operation? > > Does catching the exception, sleeping for a while, then trying again > make sense? If cursors are kept open throughout the life of the > application this would not make sense. > > > Plugin version: org.mongodb.spark:mongo-spark-connector_2.12:2.4.1 > > > --------------------------------------------------------------------- > To unsubscribe e-mail: user-unsubscr...@spark.apache.org > >
