Basic approach

Bruce Eckel's Thinking in Java Contents | Prev | Next

You should address performance only after you have a correct and fully tested program:

  1. Measure the program’s performance under realistic conditions. If it meets your requirements, you are finished. If not, go to the next step.
  2. Find the most critical performance bottleneck. This might require considerable ingenuity, but the effort will pay off. If you simply guess where the bottleneck is and try to optimize there, you’ll waste your time.
  3. Apply the speed improvement techniques discussed in this appendix, then return to Step 1.
Finding the critical bottleneck is the key to cost-effective effort – Donald Knuth [9] improved a program where 50 percent of the time was spent in less than 4 percent of the code. He changed a few lines in an hour of work and doubled the program speed. Working on the rest of the program would have dissipated his valuable time and effort. To quote Knuth, “Premature optimization is the root of all evil.” It is wise to restrain your impulses to optimize early because you may forgo many useful programming techniques, resulting in code that’s harder to understand, riskier, and requires more effort to maintain.



Comments

  • There are no comments yet. Be the first to comment!

Leave a Comment
  • Your email address will not be published. All fields are required.

Top White Papers and Webcasts

  • When individual departments procure cloud service for their own use, they usually don't consider the hazardous organization-wide implications. Read this paper to learn best practices for setting up an internal, IT-based cloud brokerage function that service the entire organization. Find out how this approach enables you to retain top-down visibility and control of network security and manage the impact of cloud traffic on your WAN.

  • Lenovo recommends Windows 8 Pro. "I dropped my laptop getting out of the taxi." This probably sounds familiar to most IT professionals. If your employees are traveling, you know their devices are in for a rough go. Whether it's a trip to the conference room or a convention out of town, any time equipment leaves a user's desk it is at risk of being put into harm's way. Stay connected at all times, whether at the office or on the go, with agile, durable, and flexible devices like the Lenovo® …

Most Popular Programming Stories

More for Developers

RSS Feeds

Thanks for your registration, follow us on our social networks to keep up-to-date