Robert Casto Software Developer and Performance Engineer

How To

• Java Tips: Optimizing your Map loop | satukubik
  By Nanda Firdausi
  From my tests, I observe that the performance of the first template depends on the backing object. If we are using HashMap, the performance is less or more the same as the second template. If we are using Hashtable, the performance of …

Java

• Java Standard Edition 6 Performance
  Java SE 6 Performance White Paper Javaâ„¢ Platform Performance Engineering Sun … and Performance Enhancements 2.1 Runtime Performance Improvements 2.11 …
• Java SE 6 Update 15
  Security and garbage collection update.
• Java SE 6 Update 16
  Security update.

Posted under Java Virtual Machine, Performance, Sun, Week in Review

Java SE 6 Update 14 Performance Improvements – One Not Free

Sun has just released Java SE 6 Update 14 with some great performance improvements.

• Optimization Using Escape Analysis : [-XX:+DoEscapeAnalysis]
  HotSpot will look for objects that are created and reference by a single thread and omit allocation treating them like local variables.
• Compressed Object Pointers : [-XX:+UseCompressedOops]
  Improves 64-bit JRE performance by compressing object references to 32 bits when the object heap is less than 32 GB.
• Garbage First (G1) Garbage Collector : [-XX:+UnlockExperimentalVMOptions -XX:+UseG1GC]
  A low pause, server style collector that is more predictable.
• Improved TreeMap Iteration : [-XX:+AggressiveOpts]
  Improved iteration for frequent passes over TreeMaps when the option is turned on.

Release notes indicate though that to use the G1 garbage collector in production, a Java support contract must have been purchased. I guess Oracle is starting to make its mark on Sun.

Posted under Java Virtual Machine, Performance, Sun, Update