Database load reducing system and load reducing program

• US 20060129528A1
• Filed: 01/14/2003
• Published: 06/15/2006
• Est. Priority Date: 01/14/2003
• Status: Abandoned Application

• Current Assignee: Accela Incorporated (Piksel Incorporated)
• Original Assignee: Accela Incorporated (Piksel Incorporated)
• Inventors: Abe, Satoshi, Miyamoto, Daisuke
• Application Number:
  US10/541,928
• Publication Number:
  US 20060129528A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2471 Distributed queries

Abstract

An object of the present invention is to provide a database load alleviation system and load alleviation program which balance load by interpreting queries and distributing queries which enable load balancing to database servers. In a database load alleviation system, a query-interpretive load balancer 1 interprets queries received from a user terminal 10, and judges whether the queries enable load balancing. Queries enabling load balancing are each distributed in sequence to one among the database servers 2-1 to 2-n in accordance with a load balancing algorithm, to balance the load. On the other hand, in the case of queries which do not enable load balancing such as a query which performs data writing, the query is replicated, and replicas are transmitted to all database servers 2-1 to 2-n, to maintain database consistency.

Claims

1. A database load alleviation system comprising:

a plurality of database servers; and

a load alleviation device which manages the plurality of database servers,

wherein the load alleviation device comprises;

a query interpretation unit which interprets received queries, and judges whether the queries enable load balancing of the database servers;

a query distribution unit which sequentially distributes and transmits to the database servers, those queries judged by the query interpretation unit to enable load balancing;

a replication unit which replicates those queries judged by the query interpretation unit not to enable load balancing; and

a query transmission unit which transmits to all managed database servers, queries replicated by the replication unit.

2. The database load alleviation system according to claim 1, wherein the query interpretation unit judges whether the received queries match a regular expression which reads data, and in the case of the regular expression which performs reading, judges the queries to be queries which enable load balancing.

3. The database load alleviation system according to claim 1, wherein the query distribution unit uses a predetermined load alleviation algorithm to select one server among the plurality of database servers, in order and in looping fashion, for distribution of a query judged by the query interpretation unit to enable load balancing.

4. The database load alleviation system according to claim 1, wherein the query transmission unit transmits the queries replicated by the replication unit to all the database servers in sequence, starting from a database server to which a next received query which enables load balancing is to be distributed, following a previously distributed query.

5. A load alleviation program, in a database load alleviation system comprising a plurality of database servers and a load alleviation device which manages the plurality of database servers, causing a computer to execute:

a function of interpreting received queries and judging whether the queries enable load balancing of the database servers;

a function of distributing and transmitting those queries judged to enable load balancing in sequence to the database servers in accordance with a load balancing algorithm;

a function of replicating those queries judged not to enable load balancing; and

a function of transmitting replicated queries to all managed database servers.