Thread Test on JRockit 28.7

JVM Tutorials - Herong's Tutorial Examples

∟Thread Test on JRockit 28.7

This section provides a tutorial example to see how many running threads can be supported on JRockit R28.2.7 JVMs.

The next test of CrashThread.java is done with JRockit R28.2.7 on my Windows 7 system.

herong> \Progra~1\java\jrockit-jdk1.6.0_45-R28.2.7-4.1.0\bin\java \
   CrashThread2.java

herong> \Progra~1\java\jrockit-jdk1.6.0_45-R28.2.7-4.1.0\bin\java \
   -Xmx16m CrashThread2 64

Time   Threads   T.Memory   F.Memory
8:54:12 PM   1   16384   14773
8:54:12 PM   2   16384   14773
8:54:12 PM   3   16384   14773

...
8:54:36 PM   60   16384   14773
8:54:37 PM   61   16384   14773
8:54:39 PM   62   16384   14773
8:54:40 PM   63   16384   14773
8:54:41 PM   64   16384   14773

Obviously there is no problem for JRockit JVM to support for 64 running threads. But I noticed that JRockit a little bit longer to launch all 64 threads comparing to HotSpot.

Then I increased # of threads to higher values, I observed the following on system Task Manager:

JRockit JVM R28.2.7
Threads   CPU    Memory   Time
     64   99%   18,500K   0.5 minutes to launch slow
    128   99%   19,552K     4 minutes to launch very slow
    256   99%   21,712K    12 minutes to launch very slow
    512   99%   22,392K    39 minutes to launch extremely slow
   1024   99%   30 672K    63 minutes to launch extremely slow