Call (800) 766-1884 for Oracle support & training
Free Oracle Tips

Oracle Consulting Support
Oracle Upgrades
Use New Oracle Features
Oracle Replication Support
Oracle Training
Remote Oracle DBA
System Documentation
Oracle Tips
Oracle Performance

Free Oracle Tips



BC Oracle tuning

Oracle training

Oracle support

Remote Oracle



  Oracle Tips by Burleson

Query Processing

The qgen program produces 22 example decision support system (DSS) queries. The queries use aggregation, subqueries, order bys and group bys to simulate the processing in a DSS environment. The queries were placed into a single file and run back-to-back in the tests. STATSPACK and custom scripts were used to monitor the database.

SSD Results

In the SSD test runs, the following configurations were tested:

  • Base run to load buffers

  • No loggingon all tables and no archive log setting

  •  No loggingon all tables with archive logging

  • Logging and archive logging

The SSD runs showed very constant times for all the various configurations after query eight was run in the base load run number one. This type of profile recurred after a shutdown startup, as shown in the graph in Figure 5.1. The entire set of seven total runs only required three days to process from May 28, 2004 through June 1, 2004. These were not run back-to-back but as time allowed. Figure 5.1 shows the comparisons of the various SSD configurations. 

As shown in Figure 5.1, even the poorest performing query, query number one, required just more than 600 seconds to complete in its worst run, run number seven. The complete query timings are shown in Table 5.1. Run number six, with archive loggingturned on, showed nearly identical query timing results as compared with previous runs, until the next to last three queries. After a restart, query number seven showed similar performance to run number one, even with archive logging turned on.  The three poorly, relative to the other SSD runs, performing queries returned to normal performance levels.

Using the SSD array, the use of loggingand archive logging had little or no effect on performance. 

The above book excerpt is from:

Oracle RAC & Tuning with Solid State Disk

Expert Secrets for High Performance Clustered Grid Computing

ISBN 0-9761573-5-7

Donald K. Burleson & Mike Ault


Oracle performance tuning software 

Oracle performance tuning book


Oracle performance Tuning 10g reference poster
Oracle training in Linux commands
Oracle training Excel
Oracle training & performance tuning books



Copyright © 1996 -  2014 by Burleson. All rights reserved.

Oracle® is the registered trademark of Oracle Corporation. 

Hit Counter