Q3: Do my secondary replicas really need to be the same level of hardware as my primary replicas?
Sean: They should, this assumes you are eventually going to fail over to them or they might need to run your workload. It does *not* assume they will be used for readable workloads. Remember that the secondary replica is already accepting and writing log data, redoing that data, and then if you’re running a bunch of read workloads on top of that it might actually be *busier* than your primary. Yes, I’ve witnessed secondary replicas getting hammered harder than their associated primary.
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