Yes, you want your clusters hot, but not too hot. For large distributed systems like Spanner you want to avoid a hotspot on a single node as that limits throug

Yes, you want your clusters hot, but not too hot. For large distributed systems like Spanner you want to avoid a hotspot on a single node as that limits throughout. However for a single-node system like PostgreSQL you want hot spots because they are cache friendly. (Locks aside) Basically you want a hotspot that is as hot as a single node can manage, but no hotter. Even for things like Spanner you still want good cache hits (which is why they support table interleaving and other methods of clustering related data) but in general avoiding overloading single nodes is more important (as it hurts latency and efficiency but doesn't limit throughput like a hotspot would).