Patent ID: 7865514
Filing Date: 2011-01-04
Classification: G06F

Abstract:
1. A computer system, comprising: a first computer that includes a database management program; a storage apparatus that includes a database that can be accessed by the database management program, the storage apparatus connected to the first computer; and a second computer that is connected to the first computer and the storage apparatus, the second computer issuing to the storage apparatus a command for commanding the storage apparatus to pre-fetch data in the database before the database management program accesses the data so that the storage apparatus receiving this command provides the pre-fetched data to the first computer, wherein the second computer includes: a first circuit that commands, when the first computer accesses the data in the database, the storage apparatus to pre-fetch the data stored in the database based on information about the access; and a second circuit that judges, when the pre-fetch is commanded, whether or not the pre-fetch will be effective, and issues the command for the pre-fetch to the storage apparatus when the pre-fetch will be effective, wherein the second circuit predicts a first required time—the time required until the pre-fetch of the pre-fetch target data is completed, and a second required time—the time required until the database management program accesses the pre-fetch target data, and wherein the second circuit compares the first required time and the second required time to judge the effectiveness of the pre-fetch.