Does MongoDB store data in memory?

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MongoDB is not an in-memory database. Although it can be configured to run that way. But it makes liberal use of cache, meaning data records kept memory for fast retrieval, as opposed to on disk. There is much bad information on StackOverflow about what to do when your server runs out of memory. 27 февр. 2019 г.

Is MongoDB stored in-memory?

MongoDB does store all its data on disk so that it can persist it during server restarts. However, it is primarily liking memory. It relies on the Operating System to schedule which bits of its database stay in memory, and which stays on disk.

How is MongoDB data stored?

MongoDB stores data objects in collections and documents instead of the tables and rows used in traditional relational databases. Collections comprise sets of documents, which are equivalent to tables in a relational database. Documents consist of key-value pairs, which are the basic unit of data in MongoDB.

Does MongoDB need lots of RAM?

MongoDB requires approximately 1 GB of RAM per 100.000 assets. If the system has to start swapping memory to disk, this will have a severely negative impact on performance and should be avoided.

Where is data stored in MongoDB?

MongoDB stores data and indexes on disk in a compressed binary format.

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