16.9: Few Advices

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We have seen a number of strategies to measure and optimize a program. The examples we have used are relatively small. Optimizing a program is not always an easy task. Identifying method candidate for inserting a cache is simple and efficient once (i) you know when to invalidate the cache and (ii) when you are aware of the impact on the overall execution when inserting the code.

In general, it is more valuable to understand the overall algorithm than trying to optimize leaf methods. The way data are structured may also provide opportunities for optimization. For example, using an ordering collection or a linked list may not be appropriated to represent acyclic graphs. Using a set may offer better performance or a dictionary in the case that hash values are reasonably well distributed.

The memory consumption may plays an important role. The overall performance may significantly decreases if the garbage collector is often solicited. Recycling objects and avoiding unnecessary object creations helps reducing the solicitation of the garbage collector.