Wrong Instance Family Wastes Cloud Spend Even When Correctly Sized

Right-sizing tools typically focus on whether cloud resources are too big or too small, but a third kind of mismatch, using the wrong instance family for a workload's resource profile, is often overlooked. An instance can show reasonable utilization numbers while its CPU-to-memory ratio is wrong for what the workload actually does. For example, a memory-heavy workload on a compute-optimized instance can waste money on unused compute capacity while delivering weaker memory performance. Catching this requires understanding the application's access patterns rather than relying solely on usage history. The article notes that family selection is the step most commonly skipped by teams that simply apply recommender suggestions.