Re: WIP: avoiding tuple construction/deconstruction overhead - Mailing list pgsql-patches

From Tom Lane
Subject Re: WIP: avoiding tuple construction/deconstruction overhead
Date
Msg-id 23924.1111071110@sss.pgh.pa.us
Whole thread Raw
In response to Re: WIP: avoiding tuple construction/deconstruction overhead  (a_ogawa <a_ogawa@hi-ho.ne.jp>)
Responses Re: WIP: avoiding tuple construction/deconstruction overhead
List pgsql-patches
a_ogawa <a_ogawa@hi-ho.ne.jp> writes:
> (1)We can improve compare_heap() by using TableTupleSlot instead of
> HeapTuple. Please see attached patch.

Did you measure any performance improvement from that?  I considered it
but thought it would likely be a wash or a loss, because in most cases
only one attribute will be pulled from a tuple during comparetup_heap.
slot_getattr cannot improve on heap_getattr in that case, and is quite
likely to be slower.

> (3)There is a description of slot->val in comment of execTuple.c.
> This had better revise it.

Drat, how'd I miss that?  Thanks.

            regards, tom lane

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