Server JVM cotinuously slow down
I wrote a benchmark to test the server VM capacity to inline code.
It works well and comparing to the client VM it's possible in my case to achieve great performance enhancement.
BUT there is something strange : during the first loop, performances are not good, then VM does its optimization resulting in better performances. the problem is that in the next loops, performances continuousy slow down ! In my code, there are nearly no memory allocation (running it with -verbosegc does no gc output).
Is someone know the reason or have encountered the same situation ?
[593 byte] By [
jcaillya] at [2007-10-3 1:33:22]

Hi!
I don't know what you are doing within your loops, but per default the server JVM hotspot compiler does the compilation (the optimization) after 10,000 iterations of a method. If you do several hundred method invocations of a few methods in your loop, it may be that after the second loop the compilation of some of those methods start. Optimal performance would be reached after each method has been executed approximately 10,000 times.
Set -XX:+PrintCompilation to watch when hotspot compiles methods.
And: The compilation threshold may be set with -XX:CompileThreshold=<value>.
Nick.