How does mongodb clear the memory it occupies

  mongodb, question

Recently, I learned to use mongodb, and found that it takes up a lot of memory. After searching online, I found that many of them use use admin. Db.runcommand ({closealldatabases: 1}) to clear memory, i found no such command in 3.0.图片描述

Is this command cancelled in 3.0 or is my method of opening incorrect? I have checked the manual and found no similar substitute command. Is this command still available in the latest version? If so, how should it be used?

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