Re: patch: fix performance problems with repated decomprimation of varlena values in plpgsql

What happened with this patch?  Alvaro saw a 25x speedup.

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Pavel Stehule wrote:
> Hello
> 
> this patch remove a multiple detoasting of varlena values in plpgsql.
> 
> It is usable mainly for iteration over longer array directly loaded
> from relation.
> 
> It's doesn't have a impact on semantic or behave - it's just eliminate
> some performance trap.
> 
> sample: table 10000 rows one column with array with 1000 string fields:
> 
> patched pl time: 6 sec
> unpatched pl time: 170 sec
> 
> This doesn't change my opinion on FOR-IN-ARRAY cycle (is still
> important for readability) - just remove one critical performance
> issue
> 
> Regards
> 
> Pavel Stehule

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