Tuning QPFRADJ

I did see a ptf cover letter that said the stuff below.  In summary it 
looks like QPFRADJ can be modified to move memory around in different time 
slots.  However does it also allow you to tailor the max amount that can 
be moved around?  Or does the APAR description cover that when it says "if 
the request is for 1 Gig or more"; meaning that it can move as much as it 
wants to, it just may move it in bigger time distributions without that 
data area set?

I think this may make a significant difference when our Domino and WAS 
servers start.
Also, since we have 11 domino servers on this beast, and the 
recommendation is 500mb/server I compromised with the boss and we used
WRKSHRPOOL
F11=Display tuning data
and set *base to 24% of our 18.3gb machine or 4.4gb.  (I suggested 38% or 
7gb.)  Not only is there Domino, but there's all that other stuff that 
runs out of *BASE.

His argument against the bigger size was that it tied up memory that could 
be used elsewhere.  My argument was that, when those servers were down 
then not much else was going on in the system other than backups, and that 
couldn't be that much of a memory hog.  When I did a WRKSYSSTS *base was 
right at 7gb.  I felt pretty happy that my guess on it's need was that 
close.  When he did it it was down to 4gb (but it was faulting and paging 
and shrpool1/qbatch had no faults and pages).  He admits that his 
performance skills may have not kept up with what the standards are for 
faulting and paging on the newer hardware and OS.  Like some people still 
believe that more disk arms is better but we've found that when we cut 
down from 42 disk arms to 7 (on our 520, not this 570) our performance was 
LOTS better.




DESCRIPTION OF PROBLEM FIXED FOR APAR SE06919 :                           
      
-----------------------------------------------                           
      
  At R510, a change was made to how often the performance                 
     
  adjuster will move memory.  At R450 and earlier, the interval           
     
  was                                                                     
     
  20 seconds where at R510, it is every 60 seconds.  If the               
     
  request                                                                 
     
  is for 1 Gig or more, 120 seconds.                                       
    
  For some workloads, this is too slow.





  SPECIAL INSTRUCTIONS FOR SUPERSEDED PTF SI07195 :
  =================================================

  To change the tuning interval, first turn the performance adjuster off:
  CHGSYSVAL SYSVAL(QPFRADJ) VALUE('0')

  Then create the following data area:
  CRTDTAARA DTAARA(QUSRSYS/QPFRADJWT) TYPE(*DEC) LEN(3 0) VALUE(60)

  In the above example, 'VALUE(60)', is the number of seconds to wait 
between
  tuning intervals.  The value can be replaced by any whole number between 
20
  and 120 (including 20 and 120).  The value can either be entered on the
  CRTDTAARA command, or by using the Change Data Area (CHGDTAARA) command.
  The data area name, library, and type must match the above command 
exactly.

  Next, turn the performance adjuster back to '2' or '3' using the 
CHGSYSVAL
  or WRKSYSVAL command.  The new interval should now take effect 
immediately.

  If you want to change the tuning interval after it has already been set,
  turn QPFRADJ system value off ('0'), change the value in the data area 
to
  the new number of seconds using CHGDTAARA, then turn the QPFRADJ system
  value back on ('2' or '3').

  ***IMPORTANT*** Deleting the QUSRSYS/QPFRADJWT data area will not change 
the
  tuning interval back to the default value of 60 seconds.  The only way 
to
  change the interval back to the default is to create (or change) the
  QUSRSYS/QPFRADJWT data area with a value of 60, and follow the previous
  instructions of turning the performance adjuster off/on.  Once the new 
value
  has taken effect, the data area may be deleted.





Rob Berendt
-- 
Group Dekko Services, LLC
Dept 01.073
PO Box 2000
Dock 108
6928N 400E
Kendallville, IN 46755
http://www.dekko.com