Re: Reviewing freeze map code

On Thu, Jun 2, 2016 at 11:24 AM, Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> Attached patch optimises skipping pages logic so that blkno can jump to
> next_unskippable_block directly while counting the number of all_visible
> and all_frozen pages. So we can avoid double checking visibility map.

I think this is 9.7 material.  This patch has already won the
"scariest patch" tournament.  Changing the logic more than necessary
at this late date seems like it just increases the scariness.  I think
this is an opportunity for further optimization, not a defect.

-- 
Robert Haas
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