Deferring some AtStart* allocations?

Hi,

In workloads with mostly simple statements, memory allocations are the
primary bottleneck. Some of the allocations are unlikely to be avoidable
without major work, but others seem superflous in many scenarios.

Why aren't we delaying allocations in e.g. AtStart_Inval(),
AfterTriggerBeginXact() to when the data structures are acutally used?
In most transactions neither will be?

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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