Performance Testing as a PM Discipline

Last year I led enterprise performance testing for a national restaurant chain's API infrastructure using k6. This was not a typical PM involvement — I was hands-on with test design, result analysis, and optimization recommendations. The experience reinforced something I have believed for years: technical program managers who understand performance testing deliver fundamentally better outcomes.

Why PMs Should Understand Performance Testing

Performance issues are the most common source of post-launch escalations I have encountered. And in nearly every case, the root cause was not that engineering failed to test — it was that the testing scope, success criteria, and production load patterns were poorly defined. That is a PM problem.

What I Learned from the k6 Engagement

Test design is a requirements exercise. Before writing a single test script, we had to define what "peak load" meant for this client. How many concurrent users? What API call patterns? What geographic distribution? These are product and business questions that engineering alone cannot answer.

Caching strategy is an architecture decision. We evaluated Valkey as a caching layer and the performance improvement was dramatic. But deciding what to cache, for how long, and with what invalidation strategy required understanding the business logic, not just the technical possibilities.

Benchmarks need business context. A 200ms API response time means nothing without context. For a menu API called during the ordering flow, 200ms is excellent. For a real-time inventory check that blocks the user, 200ms might be too slow. I established business-context-aware latency targets for every endpoint we tested.

The PM's Value Add

I wrote the performance test plan, defined the success criteria, and presented results to stakeholders. Engineering executed the tests and implemented optimizations. This division of labor worked because I could translate technical results into business impact. "P95 latency reduced from 450ms to 120ms" became "customers will experience a 73% faster ordering experience during peak lunch hours."

That translation is what makes a technical PM indispensable.