Re: Reduce TupleHashEntryData struct size by half

On 2025-Jan-14, David Rowley wrote:

> The trick would be to ensure ExecClearTuple() still works. You
> obviously don't want to try and pfree() something that isn't a pointer
> to a palloc'd chunk. I'm not sure what the best API is, but I do see
> there are other places that might benefit from something that allows
> this. The two usages of ExecCopySlotMinimalTuple() in nodeMemoize.c
> are candidates.

Maybe it would work to set a new flag in TupleTableSlot->tts_flag so
that ExecClearTuple() knows to handle it in some particular way (i.e.,
just skip the ->clear call altogether), with the idea that the tuple
memory belongs elsewhere and must not be freed by ExecClearTuple?

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Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
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