Import and Export MongoDB Data  This document provides an
overview of the import and export programs included in the
MongoDB distribution. These tools are useful when you want to
backup or export a portion of your data without capturing the
state of the entire database, or for simple data ingestion
cases. For more complex data migration tasks, you may want to
write your own import and export scripts using a client driver
to interact with the database itself. For disaster recovery
protection and routine database backup operation, use full
database instance backups.   Because these tools primarily
operate by interacting with a running mongod instance, they can
impact the performance of your running database.  Not only do
these processes create traffic for a running database instance,
they also force the database to read all data through memory.
When MongoDB reads infrequently used data, it can supplant more
frequently accessed data, causing a deterioration in performance
for the database’s regular workload.  mo