Fly.io Performance and Placement Tuning

Overview

Treat performance as an end-to-end path through Anycast routing, Fly Proxy, Machine placement, process concurrency, VM resources, autostart, and data locality. Optimize from percentiles and saturation evidence rather than assuming more regions or larger VMs always help.

Prerequisites

• Latency, throughput, error, availability, and cold-start objectives
• Per-region request, CPU, memory, concurrency, restart, and dependency latency evidence
• Current image, VM sizes, Machine counts, service concurrency, autostop, and database placement

Instructions

Step 1: Establish a representative baseline

Measure regional latency percentiles, errors, throughput, concurrency, CPU, memory, restarts, health transitions, cold starts, and dependency timing.

Step 2: Locate the bottleneck