Microsoft Corporation
CROSS DATACENTER READ-WRITE CONSISTENCY IN A DISTRIBUTED CLOUD COMPUTING PLATFORM

Abstract:

A distributed storage system including a server is configured to accept a request including a consistency indicator that flags for the server that cross datacenter consistency is desired. The server may be required to detect the consistency indicator and in response, to determine a consistency key based at least in part on the request. In an example aspect, the consistency key may comprise a hash value determined by a hash function shared across datacenters, whereby every datacenter may determine the same consistency key for a given resource and datacenter combination. The server may be further configured to determine a preferred datacenter for handling the request based at least in part on the consistency key, and thereafter to redirect the request to the preferred datacenter. In embodiments, the consistency indicator may also denote a scope of the strong consistency required by the calling client.