Running JAVA on Windows Intel vs Solaris Sparc (T1000)

Hi I'm trying to test my JAVA app on Solaris Sparc and I'm getting some weird behavior. I'm not looking for flame wars. I just curious to know what is is happening or what is wrong...

I'm running the same JAR on Intel and on the T1000 and while on the Windows machine I'm able to get 100% (Performance monitor) cpu utilisation on the Solaris machine I can only get 25% (prstat)

The application is a custom server app I wrote that uses netty as the network framework.

On the Windows machine I'm able to reach just above 200 requests/responses a second including full business logic and access to outside 3rd parties while on the Solaris machine I get about 150 requests/responses at only 25% CPU

One could only imagine how many more requests/resp开发者_运维知识库onses I could get out of the Sparc if I can make it uses full power.

The servers are...

Windows 2003 SP2 x64bit, 8GB, 2.39Ghz Intel 4 core Solaris 10.5 64bit, 8GB, 1Ghz 6 core

Both using jdk 1.6u21 respectively.

Any ideas?

The T1000 uses a multi-core CPU, which means that the CPU can run multiple threads simultaneously. If the CPU is at 100% utilization, it means that all cores are running at 100%. If your application uses less threads than the number of cores, then your application cannot use all the cores, and therefore cannot use 100% of the CPU.

Without any code, it's hard to help out. Some ideas:

• Profile the Java app on both systems, and see where the difference is. You might be surprised. Because the T1 CPU lacks out-of-order execution, you might see performance lacking in strange areas.
• As Erick Robertson says, try bumping up the number of threads to the number of virtual cores reported via prstat, NOT the number of regular cores. The T1000 uses UltraSparc T1 processors, which make heavy use of thread-level parallelism.

Also, note that you're using the latest-gen Intel processors and old Sun ones. I highly recommend reading Developing and Tuning Applications on UltraSPARC T1 Chip Multithreading Systems and Maximizing Application Performance on Chip Multithreading (CMT) Architectures, both by Sun.

This is quite an old question now, but we ran across similar issues.

An important fact to notice is that SUN T1000 is based on UltraSpac T1 processor which only have 1 single FPU for 8 cores. So if you application does a lot or even some Float-Point calculation, then this might become an issue, as the FPU will become the bottleneck.