Distributed storage system expansion mechanism

A storage cluster, comprising:

• a storage cluster having storage memory;
• the storage cluster configured to distribute data throughout the storage memory of the storage cluster in accordance a plurality of data structures in the storage cluster;
• each of the plurality of data structures having ownership of a range of the data;
• and
• the storage cluster configured to split one of the plurality of data structures, as a parent data structure, into at least a first child data structure and a second child data structure, the first child data structure having a first subset of the plurality of data structures, the second child data structure having a second subset of the plurality of data structures, wherein the storage cluster is further configured to modify the parent data structure from read and write access to read only access responsive to splitting the one of the plurality of data structures.

A storage cluster, comprising:

• a storage cluster having storage memory;
• the storage cluster having a plurality of data structures;
• each of the plurality of data structures configured to direct distribution of data throughout the storage memory;
• each of the plurality of data structures having control of a portion of the data;
• and
• the storage cluster configured to separate one of the plurality of data structures, as a parent data structure, into at least a first child data structure having a first subset of the plurality of data structures and a second child data structure having a second subset of the plurality of data structures, wherein the storage cluster is further configured to modify the parent data structure from read and write access to read only access responsive to separating the one of the plurality of data structures.