Editing Program optimization (section)

== Trade-offs ==<!-- [[Pessimization]] redirects here -->
In some cases, however, optimization relies on using more elaborate algorithms, making use of "special cases" and special "tricks" and performing complex trade-offs. A "fully optimized" program might be more difficult to comprehend and hence may contain more [[software bug|faults]] than unoptimized versions. Beyond eliminating obvious antipatterns, some code level optimizations decrease maintainability.

Optimization will generally focus on improving just one or two aspects of performance: execution time, memory usage, disk space, bandwidth, power consumption or some other resource. This will usually require a trade-off{{snd}} where one factor is optimized at the expense of others. For example, increasing the size of [[cache (computing)|cache]] improves run time performance, but also increases the memory consumption. Other common trade-offs include code clarity and conciseness.

There are instances where the programmer performing the optimization must decide to make the software better for some operations but at the cost of making other operations less efficient. These trade-offs may sometimes be of a non-technical nature{{snd}} such as when a competitor has published a [[Benchmark (computing)|benchmark]] result that must be beaten in order to improve commercial success but comes perhaps with the burden of making normal usage of the software less efficient. Such changes are sometimes jokingly referred to as ''pessimizations''.