On 4 January 2013 22:42, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Invent a "one-shot" variant of CachedPlans for better performance.
...
> Back-patch to 9.2, since this was a performance regression compared to 9.1.
> (In 9.2, place the added struct fields so as to avoid changing the offsets
> of existing fields.)
>
> Heikki Linnakangas and Tom Lane
Just a moment of reflection here but I did already invent a "one-shot"
plan concept in a patch submission to 9.2, called exactly that, which
enables a variety of optimizations, this being one.
It's a shame that my patch was deferred in favour of your approach,
yet it never happened until now, well after release. Given that I
raised this before the first CF of 9.2, that is not good.
We need a full "one-shot" concept linking the planner and executor for
all sorts of reasons, not just this one. We can discuss the
practicality of individual optimizations but the linkage should be
clear throughout the whole infrastructure.
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