Skip to Main Content
DS8800 Performance Monitoring and Tuning
book

DS8800 Performance Monitoring and Tuning

by Gero Schmidt, Bertrand Dufrasne, Jana Jamsek, Peter Kimmel, Hiroaki Matsuno, Flavio Morais, Lindsay Oxenham, Antonio Rainero, Denis Senin
July 2012
Intermediate to advanced content levelIntermediate to advanced
726 pages
26h 28m
English
IBM Redbooks
Content preview from DS8800 Performance Monitoring and Tuning
Chapter 17. Database performance 567
If RMF shows that the DFW Bypass divided by the total I/O Rate is greater than 1%, that is an
indication of NVS saturation. If this NVS saturation happens, we suggest that you set the
VDWQT to 0 or 1. Setting the VDWQT to 0 does not mean that every record update causes a
write I/O to be triggered. Because, despite the 0% threshold set, the DB2 buffer pool still has
40 buffers set aside. The last recently updated 32 buffers are scheduled for write, which
allows multiple successive updates to the same record to be not written out every time that
record is updated. This method prevents multiple write I/Os to ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

IBM System Storage DS8000 Performance Monitoring and Tuning

IBM System Storage DS8000 Performance Monitoring and Tuning

Axel Westphal, Bert Dufrasne, Wilhelm Gardt, Jana Jamsek, Peter Kimmel, Flavio Morais, Paulus Usong, Alexander Warmuth, Kenta Yuge
IBM TotalStorage DS6000 Series: Performance Monitoring and Tuning

IBM TotalStorage DS6000 Series: Performance Monitoring and Tuning

Cathy Warrick, Craig Gordon, Benoit Granier, Keitaro Imai, Rosemary McCutchen, Brannen Proctor, Jim Sedgwick, Paulus Usong, Mary Ann Vandermark, John Wickes

Publisher Resources

ISBN: 0738436836Purchase book