FAILURE TOLERANT TRANSACTION PROCESSING SYSTEM

• US 20120191681A1
• Filed: 04/04/2012
• Published: 07/26/2012
• Est. Priority Date: 11/30/2005
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Yamamoto, Guku, Tai, Hideki, Hori, Hiroshi
• Granted Patent: US 8,935,224 B2
• Time in Patent Office: Days
• US Class Current: 707/703
• CPC Class Codes: G06F 11/1443 Transmit or communication errors
• CPC Class Codes: G06F 11/1474 in transactions G06F16/20 takes precedence
• CPC Class Codes: G06F 11/183 by voting, the voting not being performed by the redundant components
• CPC Class Codes: G06F 11/2023 Failover techniques
• CPC Class Codes: G06F 9/466 Transaction processing

Abstract

The present invention proposes a system for resending a process to a backup server farm from a client without waiting for the failure-detection, if no reply is received for a certain time. The transaction processing mechanism of the present invention has a transaction start processing mechanism in which an exclusive control using a valid processing authority token and data consistency are combined, and a commit processing mechanism in which determination on whether a commit is available or not based on a distributed agreement and replication of updated data. With the mechanisms, a system for shortening a service halt time when a failure occurs to a time as such it appears to a client that the service does not stop is provided.

Claims

1. A transaction processing device in a computer system comprising a plurality of clients and a plurality of server farms connected to a network, wherein said server farm comprises at least a database, a DB server for managing the database and one or more application servers, the transaction processing device included in said DB server comprising:

a token request sending unit for sending processing authority token acquisition request message for the self server farm to acquire a right to access said database according to a transaction start request from said client via said application server;

a token reply receiving unit for receiving a reply message to said valid processing authority token acquisition request message;

a commit request sending unit for sending a commit request message; and

a commit reply receiving unit for receiving a reply message to said commit request message;

wherein said token request sending unit

sends a valid processing authority token acquisition request message to all the server farms other than said self server farm, if said self server farm does not keep the valid processing authority token and

said token reply receiving unit determines whether the valid processing authority token acquisition success or acquisition failure according to receiving a reply from a majority of server farms to said valid processing authority token acquisition request message,

said commit request sending unit sends a commit request message including a transaction log to all of said other server farms, if said valid processing authority token acquisition succeeded and,

said commit reply receiving unit determines that a commit succeeded, if an approval message is received from a majority of sever farms.

2. The transaction processing device according to the claim 12, wherein said valid processing authority token is a time-limited token including an expiration time.

3. The transaction processing device according to the claim 12, further comprising:

a valid period setting mechanism for causing said client to set a transaction resending time of a client which sends said transaction start request and a valid period of said valid processing authority token.

4. A method to acquire a right to access a database in a computer system comprising a plurality of clients and a plurality of server farms connected to a network, wherein said server farm comprises at least a database, a DB server for managing the database and one or more application servers, the method comprising:

sending a processing authority token acquisition request message for a self server farm to acquire said right to access said database according to a transaction start request from said client via an application server;

receiving a reply message to a valid processing authority token acquisition request message;

sending a commit request message;

receiving a reply message to said commit request message;

wherein;

if said self server farm does not keep a valid processing authority token, then sending said valid processing authority token acquisition request message to all the server farms other than said self server farm,

valid processing authority token acquisition success or acquisition failure is determined according to receiving a reply from a majority of server farms to said valid processing authority token acquisition request message,

if said valid processing authority token acquisition succeeds, then sending a commit request message including a transaction log to all of said other server farms, and

if an approval message is received from a majority of sever farms, then determining that a commit succeeded.

5. The method according to claim 4, wherein said valid processing authority token is a time-limited token including an expiration time.

6. The method according to claim 4, further comprising:

causing said client to set a transaction resending time of a client which sends said transaction start request and a valid period of said valid processing authority token.

7. A non-transitory storage medium for a computer program readable by a computer system, tangibly embodying a program of instructions executable by said computer system, said computer system comprising a plurality of clients and a plurality of server farms connected to a network, said server farms comprising a database (DB), a DB server for managing the database, and one or more application servers for communicating with said DB server and said clients, to perform a method to acquire a right to access said DB in said computer system, the method comprising:

sending a processing authority token acquisition request message for a self server farm to acquire said right to access said database according to a transaction start request from said client via an application server;

receiving a reply message to a valid processing authority token acquisition request message;

sending a commit request message;

receiving a reply message to said commit request message;

wherein;

if said self server farm does not keep a valid processing authority token, then sending said valid processing authority token acquisition request message to all the server farms other than said self server farm,

valid processing authority token acquisition success or acquisition failure is determined according to receiving a reply from a majority of server farms to said valid processing authority token acquisition request message,

if said valid processing authority token acquisition succeeds, then sending a commit request message including a transaction log to all of said other server farms, and

if an approval message is received from a majority of sever farms, then determining that a commit succeeded.

8. The method of the non-transitory storage medium for the computer program according to claim 7, wherein said valid processing authority token is a time-limited token including an expiration time.

9. The method of the non-transitory storage medium for the computer program according to claim 7, further comprising:

causing said client to set a transaction resending time of a client which sends said transaction start request and a valid period of said valid processing authority token.