The document discusses the limitations of traditional tier-based architectures for building scalable applications. It presents GigaSpaces' solution of using processing units that collocate services, data, and messaging in memory to minimize latency and maximize throughput. The key advantages are: 1) Services and data are collocated in a processing unit for minimal latency without network hops 2) Async persistence is used to store state changes for compliance/reporting while keeping data and services in memory 3) Resiliency is built-in through automated SLA-driven failover and redundancy between primary and backup processing units