I received a few comments on my previous blog entry saying the results were bogus since I used an old compiler. I quickly found another test system running Suse SLES 9 U2 with gcc 3.3.3 and repeated the test. If I get around to installing the latest Visual Studio I'll repeat the test there as well. The JVM versions are different as I wanted to quickly post the results. Guess what, the results are a lot better! I ran this several times and its quite repeatable. I appreciate comments so please let me know what your thoughts. Especially if there are issues with the choice of gcc 3.3.3. The system under test was a 2 x 3.0Ghz Intel Xeon MP System (4-core) running Suse SLES 9 U2 and gcc 3.3.3. The C code was compiled with full optimization as shown by the Makefile in the SciMark source package. This time no tuning parameters were used for either 5.0_08 or 6.0 b83. Here's some output from /proc/cpuinfo: vendor_id : GenuineIntel cpu family : 15 model : 4 model name : Intel(R) Xeon(TM) MP CPU 3.00GHz For background here's the skinny on SciMark2. Scimark2 is a set of simple numerical kernels and its performance is directly related to the performance and quality of the generated code. The tests are single threaded and have little to no garbage collection overhead. In short, a great set of applications to compare statically compiled C code and dynamically compiled Java. This time Java is 35% faster than C. Here's a breakdown of the subtests. C is only ahead on Sparse MatMult by a small margin. Any one interested to see how the other JVM vendors look? Can JRockit or IBM beat C?

This is quite cool. Andy Johnson, a colleague of mine on the Java performance team, did a few performance tests comparing Java to native C. SciMark2 was used for the performance comparision. The system under test was a 2Ghz Pentium white box running Windows 2000 and using the Microsoft Visual C/C++ 6. The C code was compiled with full optimization. The server compiler was used for both J2SE 5.0_07 and Java SE 6. Scimark2 is a set of simple numerical kernels and its performance is directly related to the performance and quality of the generated code. The tests are single threaded and have little to no garbage collection overhead. In short, a great set of applications to compare statically compiled C code and dynamically compiled Java. The chart below is quite revealing. Both the charts are normalized to J2SE 5.0_07. Native C is only 3% faster than 5.0_07 and Java SE 6 pulls ahead of native C by 2%. The following chart breaks the comparison down further. Remember SciMark2 is a composite benchmark and the overall score is a simple mean of each subtest mflops score. With that, Java is ahead in some cases, and behind in others. Actually Java is ahead in all cases except Sparse Matmult. Looks like we have something to look at for additional optimization.