Just finished getting the features for jcBench 0.2 completed. The big addition is the separate test of integer and floating point numbers. The reason for the addition of this test is that I heard years ago that the size of Level 2 cache directly affected performance of Floating Point operations. You would always hear of the RISC cpus having several MegaBytes of cache, while my first 1ghz Athlon (Thunderbird), December 2000 only had 256kb. As I get older, I get more and more scrupulous over things I hear now or had heard in the past thus the need for me to prove to myself one or the other.
I'm still working on going back and re-running the floating point tests so that will come later today, but here are the integer performance results. Note the y-axis is the number of seconds taken to complete the test, so lower is better.
[caption id="attachment_1097" align="aligncenter" width="300" caption="jcBench 0.2 integer comparison"]
Kind of a wide range of CPUs, ranging from a netbook cpu in the C-50, to a mobile cpu in the P920 to desktops cpus. The differences based on my current findings vary much more greatly with floating point operations.
A key things I got from this data:
- Single Threaded, across the board was ridiculously slow, even with AMD's Turbo Core technology that ramps up a core or two and slows down the unused cores. Another unsettling fact for developers that continue to not write parallel programs.
- The biggest jump was from 1 thread to 2 threads across the board
- MIPS R14000A 600mhz CPU is slightly faster than a C-50 in both single and 2 threaded tests. Finally found a very near equal comparison, I'm wondering with the Turbo Core on the C-60 if it brings it inline.
- numalink really does scale, even over the now not defined as "fast" numalink 3 connection, scaling it across 2 Origin 300s using all 8 cpus really did increase performance (44 seconds versus 12 seconds).
More to come later today with floating point results...