What are the reasons one may consider to limit the number of tables into one volume?
It’s advisable to limit the number of tables that you expect to grow beyond a trivial size within a single volume. Although, space is temporarily reserved in a container for a tablet (also called a region), the reservation expires if the tables are not created quickly.
Tablets are empty when they are allocated to containers. As a result, many tablets fit in one container. As the tablets grow, they can reach 4GB (by default). If, for example, 100 tablets are assigned to one container, the container could easily grow to 400GB. The tablets cannot be moved out of containers.
For more information about table administration, containers, and tablets, see the MapR user documentation (Administering Tables, Administering Table Regions, and Tablets and MapR-FS Containers).
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