Website performance comes in various flavours – but where to start with improvements? How to improve the performance? What are best practices to follow?

Tony Gentilcore (@tonygentilcore) talks in a blogpost about “An engineer’s guide to optimization“. Tony basically identified 5 steps to follow.

Step 1: Identify the metric. 

Identify a scenario worth being optimized – means it moves a business metric. If – after all thinking and crunching – you’re not able to identify a scenario with a clear relationship between the optimization and any business metric you should look for more pressing problems first – and revisit the performance issue later.

Step 2: Measure the metric.

After you’ve identified the metric – establish a repeatable benchmark of this scenario / metric. Include this metric measurement into your continuous integration / delivery pipelines and watch out for regressions. First, start with synthetic benchmarks and later include the real world (Real User Monitoring).

Step 3: Identify the theoretical optimum of your metric.

Think about your scenario and create a best-best-best-case. What would be the benefit, the performance maximum to gain out of the scenario. Given everything works really well, what would be the top-performance figure?

Step 4: Approach your optimium.

Identify the bottlenecks preventing you to reach the optimum. Work on these bottlenecks – start with the biggest impact first. Don’t stop optimizing until you reach a point where you have to invest more than you benefit.

Step 5: Profit from your achievements!