This topic introduces the memory structure of OceanBase Database.
As shown in the preceding figure, the total memory occupied by an OceanBase database (observer total memory) is a proportion of the server's total memory (which can also be configured as an absolute value). A portion of this memory is used for the operation of the system itself (memory reserved for OBServer internal tenant), while another portion is allocated to the created tenants (allocatable memory for observer). Each tenant is equivalent to an instance in traditional databases, and the memory modules for different tenants are the same. The memory is further divided into MemStore (tenant memstore) for storing incremental data and KVCache cache (tenant cache memory).