Alvaro Herrera <alvhe...@alvh.no-ip.org> writes: > On 2020-Nov-24, Tom Lane wrote: >>> As it stands, 0001 reduces the ParameterStatus message traffic to >>> at most one per GUC per query, but it doesn't attempt to eliminate >>> duplicate ParameterStatus messages altogether. We could do that >>> as a pretty simple adjustment if we're willing to expend the storage >>> to remember the last value sent to the client. It might be worth >>> doing, since for example the function-SET-clause case would typically >>> lead to no net change in the GUC's value by the end of the query.
>> On reflection this seems worth doing, since excess client traffic >> is far from free. > Agreed. If this is just a few hundred bytes of server-side local memory > per backend, it seems definitely worth it. Yeah, given the current set of GUC_REPORT variables, it's hard to see the storage for their last-reported values amounting to much. The need for an extra pointer field in each GUC variable record might eat more space than the actually-live values :-( regards, tom lane