Building Google Cloud Platform Solutions

Tablets and servers

Bigtable is designed to add or remove machines easily at will, and for data to be automatically rebalanced whenever needed. This is achieved through the aggressive sharding of data into tablets, which are relatively small (~200 MB) chunks of contiguous table rows. Bigtable attempts to spread tablets evenly across all nodes in your Bigtable cluster in an attempt to put a consistent load on all nodes. Bigtable regularly reschedules tablets to other nodes in an effort to maintain node stability.

When tablets grow to a sufficient size, or when tablets are subjected to high levels of IO, they are automatically split into two separate tablets, which may then be rescheduled to separate nodes as needed. Similarly, tablets that ...