Method and apparatus for sequencing transactions globally in distributed database cluster

• US 8,856,091 B2
• Filed: 02/22/2008
• Issued: 10/07/2014
• Est. Priority Date: 09/09/2005
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: Open Invention Network LLC
• Inventors: Wong, Frankie, Yu, Xiong, Wang, Elaine
• Primary Examiner(s): Abrishamkar, Kaveh
• Assistant Examiner(s): Wilcox, James J
• Application Number:
  US12/071,603
• Publication Number:
  US 20090049054A1
• Time in Patent Office: 2,419 Days
• Field of Search: None
• US Class Current: 707/703
• CPC Class Codes: G06F 11/2023 Failover techniques
• CPC Class Codes: G06F 11/2035 without idle spare hardware
• CPC Class Codes: G06F 11/2048 where the redundant components share neither address space nor persistent storage
• CPC Class Codes: G06F 11/2097 maintaining the standby controller/processing unit updated initialisation or re-synchronisation thereof G06F11/1658 and subgroups
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor
• CPC Class Codes: H04L 67/62 Establishing a time schedule for servicing the requests

Abstract

A system and method for receiving and tracking a plurality of transactions and distributing the transactions to at least two replication queues over a network. The system and method comprise a global queue for storing a number of the received transactions in a first predetermined order. The system and method also comprise a sequencer coupled to the global queue for creating a copy of each of the transactions for each of said at least two replication queues and for distributing in a second predetermined order each said copy to each of said at least two replication queues respectively, said copy containing one or more of the received transactions.

Claims

1. A system for receiving and tracking a plurality of transactions and distributing the transactions to at least two replication queues over a network, the system comprising:

a processor, wherein the processor is configured to

cause a global queue to store a number of the received transactions in a first predetermined order,

cause a sequencer coupled to the global queue to create a copy of each of the transactions for each of said at least two replication queues and distribute in a second predetermined order each said copy to each of said at least two replication queues respectively, said copy comprising one or more of the received transactions,

determine whether the global queue is full when a transaction is received, and store the transaction in a global disk queue when the global queue is full,

identify first and second transactions stored within a first of said at least two replication queues that lack sequential dependency, and

cause said first and second transactions to be distributed concurrently to a database server;

an indoubt transaction queue in communication with the sequencer, the indoubt transaction queue configured to store a transaction identified as having unknown status by a database server during a system failure; and

a resent transaction queue configured to store a transactions that repeats a request for a transaction id,

wherein each transaction of the plurality of transactions comprises at least one of a read request, an insert request, an update request, and a delete request for a record of a database.

2. The system according to claim 1, wherein the predetermined orders are selected from the group comprising:

the first predetermined order is the same as the second predetermined order; and

the first predetermined order is different from the second predetermined order.

3. The system according to claim 2, wherein the sequencer is configured to distribute each said copy at a predetermined time interval.

4. The system according to claim 2, wherein the sequencer is configured to distribute each said copy when the number of the transactions within the global queue exceeds a predetermined value.

5. The system according to claim 2, wherein the sequencer is configured to distribute each said copy upon the earlier of:

when a predetermined time interval elapses; and

when the number of the transactions within the global queue exceeds a predetermined value.

6. The system according to claim 5, wherein each of the transactions further comprises an update transaction and a unique transaction id assigned by the sequencer.

7. The system according to claim 6, wherein the global disk queue is in communication with the global queue and configured to receive and store the transactions when the global queue is above a global threshold.

8. The system according to claim 7, wherein each of said at least two replication queues have a corresponding replication disk queue configured to receive and store the transactions from the global queue when the corresponding replication queue is above a replication threshold.

9. The system according to claim 8, wherein the processor is further configured to:

determine whether the global disk queue is other than empty, and

receive the transactions from the global disk queue rather than receiving the transactions from said at least one application server when the global disk queue is other than empty.

10. The system according to claim 6, wherein the update transaction comprises the at least one of a read, insert, update or delete request for at least one database in communication with at least one of said at least two replication queues.

11. The system according to claim 2, wherein the global queue is configured for receipt of the received transactions from a network entity selected from the group comprising:

an application; and

an application server.

12. The system according to claim 2, wherein the global queue comprises a searchable first-in first-out pipe.

13. The system according to claim 12, wherein the sequencer is further configured to assure that the order of transactions in the global queue remains consistent with their execution order at a database server coupled to at least one of the replication queues.

14. The system according to claim 12, wherein the global disk queue is configured to store an indexed and randomly accessible data set.

15. The system according to claim 2, wherein the global queue and sequencer are hosted on a network entity selected from the group comprising:

a central control server and a peer-to-peer node.

16. The system of claim 1 further comprising:

a replication server configured to;

use at least two respective concurrent database connections between the first of said at least two replication queues and a secondary database of said database server to transmit the copied transaction contents to the secondary database;

distribute said first and second transactions to said database server concurrently based on said at least two respective concurrent database connections.

17. The system of claim 16, wherein the replication server is further configured to:

distribute said first transaction to said database server via a first connection of said at least two respective concurrent database connections and

distribute said second transaction to said database server via a second connection of said at least two respective concurrent database connections, wherein said first connection and said second connection are different.

18. A system for receiving a plurality of transactions from at least one application server, distributing the transactions to at least two replication queues and applying the transactions to a plurality of databases, the system comprising:

a director coupled to the at least one application server, the director configured to capture a plurality of database calls therefrom as the plurality of transactions;

a processor configured to cause a controller to receive each of the plurality of transactions, store the plurality of transactions within a global queue in a predetermined order, generate a copy of each of the plurality of transactions for each of said at least two replication queues, and transmit in the predetermined order each generated copy to each of said at least two replication queues; and

a replication server including a replication queue of said at least two replication queues, wherein the replication server is configured to distribute at least two transactions from said replication queue concurrently to a database server based on said at least two transactions lacking sequential dependency,

wherein the controller is further configured to determine whether the global queue is full when a transaction is received, and store the transaction in a global disk queue when the global queue is full,

wherein the controller is further configured to store a transaction of the plurality of transactions identified as having unknown status in an indoubt transaction queue, and

wherein the controller is further configured to store a transaction of the plurality of transactions that repeats a request for a transaction id in a resent transaction queue.

19. The system according to claim 18, further comprising:

at least two replication servers comprising said at least two replication queues, wherein

each of said at least two replication servers is coupled to each of the databases, and

the director is configured to route each of the transactions to one or more of the databases relative to the workload and transaction throughput.

20. The system according to claim 19, further comprising:

a backup controller configured to receive the transactions from said at least one application server upon failure of the controller, the backup controller comprising a backup global queue, wherein

the backup global queue is synchronized with the controller, and the backup global queue is a copy of the global queue.

21. A computer-implemented method for receiving and tracking a plurality of transactions and distributing the transactions to at least two replication queues over a network, the method comprising:

storing, by a controller, a number of the received transactions in a first predetermined order in a global queue;

determining whether the global queue is full when a transaction is received, and storing the transaction in a global disk queue when the global queue is full;

creating a copy of each of the transactions for each of said at least two replication queues;

distributing in a second predetermined order each said copy to each of said at least two replication queues respectively, said copy containing one or more of the received transactions;

providing a first transaction and a second transaction from a replication queue of said at least two replication queues to a system in parallel;

storing a transaction within an indoubt transaction queue during system failures; and

storing a transaction that repeats a request for a transaction id within a resent transaction queue,

wherein each transaction of the plurality of transactions comprises at least one of a read request, an insert request, an update request, and a delete request for a record of a database.

22. The computer-implemented method according to claim 21, wherein the distributing of each said copy occurs at a predetermined time interval.

23. The computer-implemented method according to claim 21, wherein the distributing of each said copy occurs when the number of the transactions within

the global queue exceeds a predetermined number.

24. The computer-implemented method according to claim 21, wherein the distributing of each said copy occurs upon the earlier of:

a predetermined time interval; and

the number of the transactions within the global queue exceeds a predetermined number.

25. The computer-implemented method according to claim 24, wherein each of the transactions further comprises an update transaction and a unique transaction id assigned by the sequencer.

26. The computer-implemented method according to claim 25, wherein the update transaction comprises the at least one of a read, insert, update or delete request for at least one database in communication with at least one of said at least two replication queues.

27. The computer-implemented method according to claim 24, further comprising:

receiving and storing the transactions within the global disk queue when the global queue storage capacity reaches a global threshold.

28. The computer-implemented method according to claim 24 further comprising:

determining when at least one of said at least two replication queues are above a replication threshold, each of said at least two replication queues having a corresponding replication disk queue;

storing a number of the transactions within said corresponding replication disk queue based upon the determination; and

sending an alert to notify when said at least two replication queues and said corresponding replication disk queue capacity reach a preselected threshold.

29. The computer-implemented method according to claim 28, further comprising:

redirecting the transactions to at least one of said at least two replication queues being below said preselected threshold, based on receiving the alert.

30. The computer-implemented method according to claim 21, further comprising:

determining whether the global disk queue is other than empty; and

receiving the transaction from the global disk queue rather than receiving the transactions from said at least one application server when the global disk queue is other than empty.

31. A system for receiving and tracking a plurality of transactions and distributing the transactions to at least two replication queues over a network, the system comprising:

a processor configured to

store a number of the received transactions in a first predetermined order,

create a copy of each of the received transactions for each of said at least two replication queues,

distribute, in a second predetermined order, each said copy to each of said at least two replication queues respectively, said copy comprising one or more of the received transactions,

store a transaction having an unknown status within an indoubt transaction queue, and

store a transaction that repeats a request for a transaction id within a resent transaction queue; and

a replication server including at least one replication queue of said at least two replication queues and configured to concurrently provide a set of transactions from said at least one replication queue to a database server based on the set of transactions having no sequential dependency,

wherein the processor is further configured to determine whether the global queue is full when a transaction is received, and store the transaction in a global disk queue when the global queue is full, and

wherein each transaction of the plurality of transactions comprises at least one of a read request, an insert request, an update request, and a delete request for a record of a database.