benchmarking proposed config

Does anyone have suggestions for a utility that would easily let us mirror all queries to a "shadow" PG cluster, so that we can compare performance of our current production config against a new proposed config with our actual production traffic?

(We could live with the new one falling behind as long as queries were queued not lost--in fact we know this will happen.)

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Scott Ribe
scott_ribe@elevated-dev.com
https://www.linkedin.com/in/scottribe/