Patent ID: 8880477

Claim:
A method for migration from a multitenant database, comprising: taking a snapshot of an original database to be migrated with a hot backup process, such that the database is still capable of answering queries during the hot backup process; selecting a database migration method that does not generate a service level agreement (SLA) violation and otherwise selecting a method that generates the fewest SLA violations during the database migration; applying a proportional-integral-derivative (PID) controller to determine a speed of migration based on system performance, wherein the PID controller has a proportional path, an integral path and a derivative path, each path is scaled by coefficients K p , K i , and K d respectively, wherein an output at time t with error e(t) is given by: output ⁡ ( t ) = K p ⁢ e ⁡ ( t ) + K i ⁢ ∫ 0 t ⁢ e ⁡ ( τ ) ⁢ ⅆ τ + K d ⁢ ⅆ e ⁡ ( t ) ⅆ t ; maintaining a query log of all queries to the tenant database after the hot backup process begins; initializing a new database at a target server using the snapshot; replaying the query log to synchronize the new database with the original database; and answering new queries with the new database and not the original database.