We've made experiments, but the usage of this tier is still being considered. One of the proposals is: - use it to simplify the cache instead of local SSDs; -

We've made experiments, but the usage of this tier is still being considered. One of the proposals is: - use it to simplify the cache instead of local SSDs; - it has to be in every AZ where there are replicas; the caches will work independently in each AZ; - so it might be expensive, but if we make replica initialization time close to zero and have no local metadata at all, we can afford to run in one AZ at any moment in time and still have failover to another AZ with the cost of losing the cache. PS. Snowflake has virtual warehouses in a single AZ by default. ClickHouse Cloud has nodes in three AZ (prod tier) or two AZ (dev tier).