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  • Your email address will not be published.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

  • Live Event Date: January 28, 2015 @ 11:00 a.m. ET / 8:00 a.m. PT Check out this upcoming live webcast and join Jeff Sloyer, IBM Developer Evangelist and Master Inventor, for a tutorial for building cloud-based applications. Using IBM's platform as a service, Bluemix, Jeff will show you how to architect and assemble cloud-based applications built for cloud scale. Leveraging the power of microservices, developers can quickly translate monolithic applications to a cloud-based microarchitecture. This hour-long …

  • Data integrity and ultra-high performance dictate the success and growth of many companies. One of these companies is BridgePay Network Solutions, a recently launched and rapidly growing financial services organization that allows merchants around the world to process millions of daily credit card transactions. Due to the nature of their business, their IT team needed to strike the perfect balance between meeting regulatory-mandated data security measures with the lowest possible levels of latency and …

Most Popular Programming Stories

More for Developers

RSS Feeds

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