Method and system for data processing with connection pool for the same

• US 20070198684A1
• Filed: 07/18/2006
• Published: 08/23/2007
• Est. Priority Date: 02/22/2006
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Mizushima, Kazunori
• Application Number:
  US11/488,026
• Publication Number:
  US 20070198684A1
• Time in Patent Office: Days
• US Class Current: 709/223
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

When an application server prepares the connection made to the database server, an identifier for definitely identifying the database server of connection destination is allotted to the connection. When a fault occurs in a database system, the database identifier of the connection is specified and only a connection allotted with the same identifier as the specified identification is discarded from a connection pool. When a request is received from a client computer, a connection is acquired from the connection pool. The acquired connection is decided as to whether to be faulty and if the acquired connection is determined as being faulty, a database server to be coupled to the faulty connection is specified by consulting connection management information. All connections made or coupled to the specified database server are discarded from the connection pool and a new connection is prepared.

Claims

1. A database connection managing method for use in a computer system having a database system provided with a plurality of database servers each including a database management system, an application server provided with a connection pool for retaining a plurality of connections to be made to the database system and operative to access said database system, and a client computer for accessing said application server to receive an offer of business service, wherein

said database system stores said database server to be connected to said application server within said application server and said database system makes connection to said application server;

and

said application server retains connection management information for specifying, when preparing a new connection, a database server to be connected to the prepared connection and managing said specified database server and said prepared connection by making the correspondence therebetween.

2. A database connection managing method according to claim 1, wherein when receiving a request from said client computer, said application server acquires a connection from said connection pool, decides whether said acquired connection is faulty, and when said acquired connection is determined to be faulty, consults said connection management information to specify a database server to be coupled with said faulty connection, discards all connections to be made to said specified database server from said connection pool and prepares a new connection.

3. A database connection managing method according to claim 1, wherein when receiving a request for blocking a database server, said application server consults said connection management information to decide whether a connection made to said database server to be blocked is occupied, and when the result of decision indicates that said connection is occupied, sets the state of said connection in said connection management information to “

scheduled for discard”

but with the unoccupied state of said connection determined, discards said connection.

4. A database connection managing method according to claim 3, wherein when receiving the request for blocking a database server, said application server decides whether said database server to be blocked is registered in said connection management information, and if the result of decision does not indicate that said database server to be blocked is registered, notifies an error.

5. A database connection managing method according to claim 3, wherein when receiving a request for releasing a connection, said application server consults said connection management information to decide whether the state of the connection to be released is scheduled for discard, and if the result of decision determines that the state of said connection to be released is scheduled for discard, discards said connection but if the state of said connection to be released is not scheduled for discard, changes the state of said connection to “

unoccupied”

.

6. A database connection managing method according to claim 1, wherein said application server includes a display unit for displaying said connection management information.

7. A database connection managing method according to claim 1, wherein when receiving a request for adding a database server, said application server consults said connection management information to specify unoccupied connections and discards one of said specified unoccupied connections which is coupled to a highly-loaded database server.

11. A database connection managing method according to claim 1, wherein said computer system includes a connection unit for relaying an access to said database system from said application server, said connection unit monitors a load on said database server and retains information on the load acquired through monitoring, and said application server consults, when receiving a request from said client computer, the load information retained in said connection unit to preferentially acquire a connection for a lower-loaded database server from said connection pool.

12. A database connection managing method according to claim 1, wherein said computer system includes a connection unit for relaying an access to said database system from said application server, said connection unit monitors the state of occupation of a connection by said application server to retain connection occupation information acquired through monitoring, and said application server consults, when receiving a request from said client computer, the connection information retained in said connection unit to acquire the same connection as used by said application server from said connection pool.

8. An application server comprising:

a processor for performing operation processes;

a memory connected to said processor; and

a communication interface connected to said processor, wherein

said application server responds to an access from a client computer receiving an offer of business service from said application server to access a database system including a plurality of database servers;

said database system includes a database management system, so that a database server connected to said application server may be memorized in said application server and connects said database server to said application server; and

said application server includes a connection pool for retaining a plurality of connections made to said database system, and wherein

said processor retains connection management information for specifying, when preparing a new connection, a database server connected to the prepared connection and managing said specified database server and said prepared connection by making the correspondence therebeteen.

9. A program for causing an application server having a processor adapted to perform operation processes, a memory connected to said processor and a communication interface to manage connection to a database,

wherein said application server includes a connection pool for retaining a plurality of connections made to said database system and responds to an access from a client computer receiving a business service from said application server to select a connection from said connection pool;

wherein said database system includes a plurality of database servers each having a database management system, with a database server to be connected to said application server being memorized in said application server for connection thereto; and

wherein said program causes said application server to execute a step of specifying, when said application server prepares a new connection, a database server coupled to the prepared connection and a step of retaining connection management information for managing said specified database server and said prepared connection by making the correspondence therebetween.

18. A program according to claim 9, wherein said program causes said application server to execute the steps of:

consulting, when receiving a request for blocking a database server, said connection management information to decide whether the connection made to the database server to be blocked is occupied; and

setting the state of said connection in said connection management information to “

scheduled for discard”

when the result of decision indicates that said connection is occupied but discarding said connection when said connection is determined to be unoccupied.

19. A program according to claim 18, wherein said program causes said application server to execute the steps of:

deciding, when receiving a request for blocking a database server, whether said database server to be blocked is registered in said connection management information; and

notifying an error when the result of decision indicates that said database server to be blocked is not registered.

20. A program according to claim 19, wherein said program causes said application server to execute the steps of:

consulting, when receiving a request for releasing a connection, said connection management information to decide whether the state of the connection to be released is scheduled for discard; and

discarding said connection when the result of decision indicates that the state of said connection to be released is scheduled for discard but changing the state of said connection to “

unoccupied”

when the state of said connection to be released is not scheduled for discard.

10. A computer system comprising a database system having a plurality of database servers and a distributor, an application server for making an access to said database system and a client computer for accessing said application server to receive an offer of business service,

wherein said application server includes a processor for performing operation processes, a memory connected to said processor, a communication interface connected to said processor and a connection pool for retaining a plurality of connections to be coupled to said database system;

wherein said database system includes a distributor for distributing accesses to said plurality of database servers to each of them;

wherein said distributor distributes accesses to said plurality of database servers by causing a database server subject to coupling to be memorized in said application server and by coupling it to said database server;

wherein said database server includes a processor for performing operation processes, a memory connected to said processor and a communication interface coupled to said processor;

wherein said processor of database server executes a database management system; and

wherein said processor of application server retains connection management information for specifying, when preparing a connection, a database server to be coupled to the prepared connection and managing said specified database server and said prepared connection by making the correspondence therebetween.

13. A computer system according to claim 10, wherein said application server includes:

means for acquiring a connection from said connection pool when receiving a request from said client computer;

means for deciding whether said acquired connection is faulty; and

means for consulting, when said acquired connection is determined to be faulty, said connection management information to specify a database server to be coupled to said faulty connection, discarding all connections to be coupled to said specified database server from said connection pool and preparing a new connection.

14. A computer system according to claim 13, wherein said application server includes:

means for consulting, when receiving a request for blocking a database server, said connection management information to decide whether a connection to be coupled to said database server to be blocked is occupied; and

means for setting the state of said connection in said connection management information to “

scheduled for discard”

when the result of decision indicates that said connection is unoccupied but discarding said connection when said connection is occupied.

15. A computer system according to claim 14, wherein said application server includes:

means for deciding, when receiving a request for blocking a database server, whether the database server to be blocked is registered in said connection management information; and

means for notifying an error when the result of decision indicates that said database server to be blocked is not registered.

16. A computer system according to claim 15, wherein said application server includes:

means for consulting, when receiving a request for releasing a connection, said connection management information to decide whether the state of the connection to be released is scheduled for discard; and

means for discarding said connection when the result of decision indicates that the state of the connection to be released is schedule for discard but changing the state of the connection to “

unoccupied”

when the state of the connection to be released is not scheduled for discard.

17. A computer system according to claim 10, wherein said application server includes:

means for acquiring, when receiving a request from said client computer, a connection from said connection pool;

means for deciding whether said acquired connection is faulty; and

means for consulting, when said connection is determined to be faulty, said connection management information to specify a database server coupled to said faulty connection, discarding all connections made to said specified database server and preparing a new connection.