A lot of people talk about the performance comparison of some languages by referring to the tests on shootout.alioth.debian.org . The thing is, I don't know how to read the results. The image seems incomprehensible, as I can't seem to find a NORMAL legend. Can you explain one of the tests, with a image? Choose whatever languages you want.
+2
A:
All results are ratios between the speed / memory usage / source code size of the given programs in the two chosen languages.
Take Perl vs. Ruby, for example. Every benchmark is expressed in a ratio Perl / Ruby. For the mandelbrot program, the Perl implementation completed 8 times faster than the Ruby implementation. The result therefore is 1/8. This is then marked in the graph at the 1/8 point. The memory usage is actually better in Ruby, with a factor of 191.
The result of this is that the line marked by 1 indicates that the two chosen languages are equal in performance / memory usage / source code size, with the given implementations. Every value below 1 (downwards) means that the first mentioned language is faster / consumes less memory / is smaller. Everything above 1 (upwards) means that the latter language is faster, etc.
The vertical scale is logarithmic, meaning that small bars mean little difference, while long bars mean enormous difference.
All the vertical bars per measurement unit represent all the benchmarks that exist for this comparison, ordered from good to bad.
I hope this helps.
molf
2009-07-06 21:21:46