Re: Variable-length FunctionCallInfoData

On 6/5/18 13:29, Andres Freund wrote:
> Besides the change here, I think we should also go much further with the
> conversion to NullableDatum.  There's two main areas of change: I want
> to move the execExpr.c related code so steps return data into
> NullableDatums - that removes a good chunk of pointer dereferences and
> allocations. Secondly I think we should move TupleTableSlot to this
> format - the issue with nulls / datums being on separate cachelines is
> noticeable in profiles, but more importantly the code looks more
> consistent with it.

There are also a variety of utility functions that return a Datum and
have an extra bool *isnull argument.  What are your thoughts on using
NullableDatum more in those cases?  Is returning structs a problem for
low-level performance?

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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