Patent ID: 8655971
Filing Date: 2014-02-18
Classification: G06F

Abstract:
1. A method for breaking locks held by a two-phase commit transaction while preserving data consistency, the method comprising: transmitting a first message to prepare for a transaction associated with a data object to each of two or more servers that include one or more lower-priority servers and a higher-priority server, wherein each of the two or more servers is associated with a separate representation of the data object; monitoring for reply messages from the one or more lower-priority servers in response to receiving the first message, wherein the reply messages from a lower-priority server indicates whether the lower-priority server is able to complete the transaction associated with the data object; if a reply message has not been received from at least one of the lower-priority servers in response to the first message, transmitting a second message to the higher-priority server that causes the higher-priority server to leave the data object associated with the higher-priority server unmodified; and if a reply message is received from each of the lower-priority servers, transmitting a third message to the higher-priority server that causes the higher-priority server to modify the representation of the data object associated with the higher-priority server; wherein the first, second, and third messages are transmitted from a two-phase commit (2PC) coordinator and the reply messages are monitored by the 2PC coordinator; and wherein the 2PC coordinator resides and executes on the higher-priority server.