Tom Lane wrote:
Heikki Linnakangas <[EMAIL PROTECTED]> writes:
The number of buffers evicted by normal backends in a bgwriter_delay period is simple to keep track of, just increase a counter in StrategyGetBuffer and reset it when bgwriter wakes up. We can use that as an estimate of X with some safety margin.


You'd want some kind of moving-average smoothing in there, probably with
a lot shorter ramp-up than ramp-down time constant, but this seems
reasonable enough to try.

Ironically, I just noticed that we already have a patch in the patch queue that implements exactly that, again by Itagaki. I need to start paying more attention :-). Keep up the good work!

--
  Heikki Linnakangas
  EnterpriseDB   http://www.enterprisedb.com

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