James Gosling blogs about Java software performance myths and posts an interesting story (below). The comments contains few more stories from the trenches as they say. Lets look at the real picture shall we? There was a funny incident at a recent developer event where some folks had a booth where they where demo-ing a high end industrial strength C compiler and had a benchmark that they had transliterated into Java. They were comparing their compiler to GCC and Java. GCC was running at about 2/3 the performance of this high end compiler; the Java version was running at about 2/3 the performance of the GCC version. Folks were gathered around the booth and someone noticed that the script they were using to run the Java version didn't have optimisation turned on. A few seconds with vi to add the "-server" switch and Java's performance jumped up to match the fancy C compiler. This got the pro-GCC crowd all excited, so a bunch of them started fiddling with its command line switches. They got a bit of improvement, but not much (the original selection had been pretty good). Author: James Gosling from Sun