Re: Do we really need to switch to per-tuple memory context inATRewriteTable() when Table Rewrite is not happening

Ashutosh Sharma wrote:

> I am basically talking about the following lines of code in
> ATRewriteTable() function.
> 
> /*
>  * Switch to per-tuple memory context and reset it for each tuple
>  * produced, so we don't leak memory.
>  */
> oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));

Perhaps a memory context switch is so cheap that adding a branch to
verify whether it's needed is more expensive than just doing it all the
time.  You could prove me wrong by measuring it.

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Álvaro Herrera                https://www.2ndQuadrant.com/
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