Keyspaces

A keyspace is a namespace with its own memory budget, TTL default and eviction policy. Services never share a keyspace.

Configured

Keyspace	Owner	Budget	Used	TTL default	Eviction
session:*	auth	180 GB	174 GB	12 h	lru, warm
rate:*	edge	24 GB	9 GB	60 s	ttl only
frag:*	web	220 GB	186 GB	30 m	lru
geo:*	dispatch	48 GB	31 GB	24 h	lru
tmp:*	shared	16 GB	4 GB	5 m	ttl only

Budgets

A keyspace over budget evicts inside itself only — it cannot push another service out.
ttl only means nothing is evicted early; writes fail once the budget is reached. Use it where a stale answer is worse than no answer.
Raising a budget takes effect on the next gossip round, no restart.

session:* has been within 4% of its budget for a week. Either raise the budget or shorten the default TTL — eviction at this rate costs more in re-auth than the memory is worth.