DBA Tips Archive for Oracle
Faster database exports/imports
by Jeff Hunter, Sr. Database Administrator
The import and export programs (imp/exp) run in two task mode to protect the SGA from potential corruption by user programs. By relinking these two programs in single task mode you can gain much improvement in speed. In many cases up to 30%. Oracle themselves use this method although it is NOT supported by Oracle.
Running in single-task is much faster but it requires more memory since the Oracle executable's text is no longer shared between the front-end and background processes. If you need to transfer large amounts of data between databases, relink the executale for greater efficiency.
To relink the RDBMS kernel and create the two new imp/exp programs, use the following:
% cd $ORACLE_HOME/rdbms/lib % make -f ins_rdbms.mk singletask % make -f ins_rdbms.mk expst % make -f ins_rdbms.mk impst % make -f ins_rdbms.mk sqlldrst % mv expst $ORACLE_HOME/bin/ % mv impst $ORACLE_HOME/bin/ % mv sqlldrst $ORACLE_HOME/bin/Now use expst and impst instead of imp or exp.
Copyright (c) 1998-2017 Jeffrey M. Hunter. All rights reserved.
All articles, scripts and material located at the Internet address of http://www.idevelopment.info is the copyright of Jeffrey M. Hunter and is protected under copyright laws of the United States. This document may not be hosted on any other site without my express, prior, written permission. Application to host any of the material elsewhere can be made by contacting me at firstname.lastname@example.org.
I have made every effort and taken great care in making sure that the material included on my web site is technically accurate, but I disclaim any and all responsibility for any loss, damage or destruction of data or any other property which may arise from relying on it. I will in no case be liable for any monetary damages arising from such loss, damage or destruction.