Momento Cache, an open-core caching engine built on Twitter's Pelikan, has been optimized for Google's Arm-based Tau T2A VMs to enhance performance and developer productivity by focusing on consistent tail latencies. By rewriting Pelikan in Rust and implementing multi-worker support, the team achieved significant throughput improvements without modifying the code, primarily through strategic systems tuning like core pinning. This approach allowed them to reach over a million operations per second (OPS) on a single T2A-standard-16 VM while maintaining a 2ms service-level objective (SLO). The optimizations, which included isolating network threads to specific cores, not only tripled the throughput but also significantly reduced tail latencies, offering a high return on investment for those concerned with performance at high loads. These tuning techniques also benefited x86-based C2 VMs, though the improvements were slightly less dramatic, showcasing the potential of core pinning in optimizing cache performance across different architectures.