How to limit MongoDB memory usage

howto.md

If you are running MongoDB 3.2 or later version, you can limit the wiredTiger cache.

In /etc/mongod.conf add the wiredTiger part:

storage:
  dbPath: /var/lib/mongodb
  journal:
    enabled: true
  wiredTiger:
    engineConfig:
        cacheSizeGB: 1

That will limit the cache size to 1GB, more info in Doc

After changing the config, restart the mongo daemon.

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