International Business Machines Corporation

Justin T Fries

Lohitashwa Thyagaraj

Rajesh C Lalgowdar

Venkataraghavan Lakshminarayanachar

Timothy M C McCormick

Release and re-acquisition of each of a first shared lock on an outer database ownership table and a second shared lock on an inner database ownership table is alternated by a messaging engine processor that executes a messaging engine to permit database maintenance operations to be performed while maintaining the ownership of the database. At least one period of inactivity of both the outer database ownership table and the inner database ownership table is provided that allows at least one database tool to execute to perform at least one database maintenance task during the execution of the messaging engine.

Management of long-running locks and transactions on database tables

An exclusive lock is acquired on each of an outer database ownership table and an inner database ownership table to obtain ownership of a database. The exclusive locks are converted to a pair of overlapping shared locks on each of the outer database ownership table and the inner database ownership table, where release and re-acquisition of each of the pair of overlapping shared locks on the outer database ownership table and the inner database ownership table permits database maintenance operations to be performed while maintaining the ownership of the database.

As disclosed herein is a tool for preventing split-brain scenario, including determining, by a processor, that a first node of a HA cluster is unable to communicate with a second node of the HA cluster, and initiating, by a processor, by the first node, a handshake operation with a connected client, wherein the handshake operation comprises requesting that the client determine a status of the second node and receiving, from the client, a response indicating the status of the second node. Further, accepting, by a processor, new requests in response to determining that the second node is unavailable, and requesting, by a processor, restoration of communications between the first node and the second node in response to determining that the second node is available.

Preventing split-brain scenario in a high-availability cluster

As disclosed herein a method, executed by a computer, includes determining, by a processor, that a first node of a HA cluster is unable to communicate with a second node of the HA cluster, and initiating, by a processor, by the first node, a handshake operation with a connected client, wherein the handshake operation comprises requesting that the client determine a status of the second node and receiving, from the client, a response indicating the status of the second node. The method further includes accepting, by a processor, new requests in response to determining that the second node is unavailable, and requesting, by a processor, restoration of communications between the first node and the second node in response to determining that the second node is available. A computer system and computer program product corresponding to the above method are also disclosed herein.

Establishment of an exclusive lock on each of an outer database ownership table and an inner database ownership table is attempted. In response to establishing the exclusive lock on each of the outer database ownership table and the inner database ownership table, a switch is made to a pair of overlapping shared locks on each of the outer database ownership table and the inner database ownership table. Release and re-acquisition of each of the pair of overlapping shared locks on the outer database ownership table and the inner database ownership table is alternated.

Growing community of inventors

Raleigh, NC, United States of America

Justin T Fries