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MPW system parameter values?

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The Question is:

Due to MC SYSGEN HELP MPW_*LIMIT, a system deadlock occurs if MPW_WAITLIMIT is
 less than MPW_HILIMIT.
Then why is AUTOGEN calculating MPW_HILIMIT to 32768 and MPW_WAITLIMIT 13363,
 which is less?
Does it make any sense if MPW_WAITLIMIT is set higher than MPW_HILIMIT?

The Answer is :

  AUTOGEN originally calculated MPW_HILIMIT as 32768.  It was then
  directed to use tha hardcoded value of 13107.
  Based on this forced MPW_HILIMIT value, AUTOGEN calculated the
  MPW_WAITLIMIT value as 13363 -- which is higher than MPW_HILIMIT
  and which would avoid a possible deadlock.
  Regarding "Does it make any sense if MPW_WAITLIMIT is set higher than
  MPW_HILIMIT?", yes.  Writing of modified pages starts when the size of
  the modified page list exceeds MPW_HILIMIT.  There are certainly other
  reasons to write modified pages, but they do not particularly apply here.
  Processes are placed into the RWMPB wait state when the process places
  a page on the modified page list and the size of the modified list
  exceeds MPW_WAITLIMIT.  Again, there are more reasons, but...
  By making MPW_WAITLIMIT larger than MPW_HILIMIT, the modified page
  writer gets a head start on reducing the modified page list and it is
  less likely that processes will have to wait in RWMPB.

answer written or last revised on ( 29-MAR-2002 )

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