Case Study: Signal achieves 68% TCO reduction and 100x p99 performance improvement with Aerospike

How Signal Replaced Open Source Cassandra with Aerospike for Superior TCO and Operations

Signal, a leading SaaS provider for data onboarding and real-time identity resolution, was struggling with an open-source Cassandra deployment that had grown into a costly, high-touch 450+ node footprint. The cluster suffered unpredictable latency and uptime that hurt SLAs and diverted engineering time to "care and feeding" rather than new features. Signal needed a more reliable, real-time architecture with cross-datacenter replication, a smaller operational footprint, and much better p99 read/write performance.

Signal selected Aerospike for its Hybrid-Memory Architecture and ease of scaling. After migration, node count dropped from 450 to 60, driving a 68% TCO reduction over three years and freeing engineering resources. Performance improved dramatically (p99 from ~3,900 ms to 23 ms and p50s as low as 10 µs at peak loads), enabling 8M TPS tests, 10x–60x faster business processes, and more predictable, reliable real-time identity services.

Signal

Jason Yanowitz

EVP, Chief Technology Officer