Decision: strip the customisations, externalise the cache
Stress tests at 50 authentications per second over 10-minute windows exposed the cost of history: the custom code layered onto Keycloak 15 introduced severe latencies. The fix was subtraction — remove the customisations (rework 2FA), externalise the session cache, move from CentOS VMs to Kubernetes (Q3 2023). Keycloak 19/20 then cut memory and network consumption drastically. The lesson the note preserves: the slowness was self-inflicted.
Topology
- Part of: identity-architecture
- About: cern-sso
- Depends on: decision-leave-adfs — custom code is what killed ADFS too; this time it was removed instead of accumulated.
- Cites: why-keycloak — test figures and remediation steps.