RE: [MI400] What is main memory resident?

["Kaare Plesner, SOSY A/S" <kaaple@xxxxxxxxxxxxx>]

Thanks to all of you for your comments.
Since no-one had a suggestion how to actually verify what is in main memory
I take that this is not possible, or at least not very simple - which was
what I suspected.

Answer to Kevin: The "knowing" would confirm that I had chosen the right
method to keep what I wanted in memory, which again would guarantee a top
performance.

Answer to Leif: You of course am right, I am trying to optimize performance
by cutting out waits for physical reads. I am familiar with SETOBJACC, but I
do not want an entire data base file preloaded, only certain parts.

Answer to Walden: You are right in your comments that storage management and
expert cache often will do the job for you, but it obviously cannot always
predict what you will be needing.
Performance tools and iDoctor can give you a report of physical I/Os per
object, but are a bit heavy on the machine when used.

Answer to Mark: Thanks for your suggestions - I am testing such methods and
wanted to verify the degree of success.
But I cannot agree with you on advising customers to turn QPFRADJ off - I
absolutely used to say the same, but since IBM around 3 years ago
implemented a completely new tuning algorithm and allowed user parameters
for e.g. lower and upper limits for pool sizes then I today firmly believe
that close to all machines will benefit from switching this tuner on!

Answer to Paul: Thank you for your input on storage management - but I take
it that "if turned on, QPFRADJ may move pages between pools" still does NOT
apply for private pools??

Kaare Plesner        I     SOSY A/S
mailto:kp@sosy.dk    I     DK-2730 Herlev
                     I     Denmark
    SOSY A/S - an IBM Business Partner
      Meet us at http://www.sosy.dk/