I wrote: > Heikki Linnakangas <[EMAIL PROTECTED]> writes: >> If there's no easy solution, I think we could live >> with that, but Greg's suggestion of bumping the usage_count in PinBuffer >> instead of UnpinBuffer sounds like a nice solution to me.
> After thinking about it more, I'm a bit hesitant to do that because it
> will change the interaction with the clock sweep for buffers that stay
> pinned for awhile. I had suggested making the clock sweep not decrement
> usage_count of a pinned buffer, but I think that would change the
> fairness of the algorithm. OTOH it may not matter that much if we just
> move the usage_count increment and leave the clock sweep alone. Do we
> have any decent way of measuring the effectiveness of the clock-sweep
> allocation algorithm?
Despite above misgivings, here's a version of the patch that moves
usage_count incrementing to PinBuffer instead of UnpinBuffer. It does
seem a good bit cleaner.
regards, tom lane
binalDuLkt1Ft.bin
Description: buffer-ring-3.patch.gz
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