Bruce Momjian wrote:
> Tom Lane wrote:
>> The suggestions that were made upthread about moving the hint bits
>> could resolve the second objection, but once you do that you might
>> as well just exclude them from the CRC and eliminate the guessing.
> OK, crazy idea #3. What if we had a per-page counter of the number of
> hint bits set --- that way, we would only consider a CRC check failure
> to be corruption if the count matched the hint bit count on the page.
Can I piggy-back on Bruce's crazy idea and ask a stupid question?
Why are we writing out the hint bits to disk anyway? Is it really so
slow to calculate them on read + cache them that it's worth all this
trouble? Are they not also to blame for the "write my import data twice"
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