Browse Prior Art Database

Combined DASD Driver and Relational Data Base Manager

IP.com Disclosure Number: IPCOM000108229D
Original Publication Date: 1992-May-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 3 page(s) / 113K

Publishing Venue

IBM

Related People

Boardman, TJ: AUTHOR [+2]

Abstract

Relational Data Base Management Systems (RDMS) are constrained by inefficient use of DASD in AIX*. Disclosed is a computer system including a RDMS which is combined with the DASD driver. In current systems, RDMSs running on AIX generate commands which must traverse many layers of AIX kernel software before they reach the DASD.

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Combined DASD Driver and Relational Data Base Manager

       Relational Data Base Management Systems (RDMS) are
constrained by inefficient use of DASD in AIX*.  Disclosed is a
computer system including a RDMS which is combined with the DASD
driver.  In current systems, RDMSs running on AIX generate commands
which must traverse many layers of AIX kernel software before they
reach the DASD.

      In the new system, applications use SQL functions in the same
way as now but multiple crossings of the application to kernel
interface are avoided.  Currently, an SQL function may involve many
thousands of application to kernel interface crossings taking
significant time.  But now only one crossing of the application to
kernel interface per SQL function is required.

      A DASD device driver has both an application interface and a
hardware interface.  For the combined DASD driver and Relational Data
Base Management System (CDDRDMS) the hardware interface would be the
same as for an individual DASD driver.

      The application interface comprises the following functions:
*    to connect to a data base,
*    to perform all SQL statements to maintain and access a data
base,
*    to disconnect from a data base.

      These functions will allow programs with embedded SQL
statements to directly access the CDDRDMS.

      Thus, the CDDRDMS contains a complete RDMS.  Existing RDMSs
running on AIX generate open, write, read and close commands to a
DASD driver which must traverse many layers of AIX kernel software
before they reach the DASD.  Also, many reads and writes must be
performed for each SQL statement encountered.  With CDDRDMS the extra
AIX layers can be avoided and the system performance for database
operati...