JVM Tutorials - Herong's Tutorial Examples
Dr. Herong Yang, Version 4.10

Thread Testing Result with JDK 1.6.0

This section describes thread test results with JDK 1.6.0.

After installing JDK 6u2, I tested the CrashThread program again on a Windows XP system. Here are the results.

Both HotSpot Client and HotSpot Server 1.6.0_02 have no problem with 16 threads.

With 32 threads running, HotSpot Client 1.6.0_02 took 99% of the CPU time according to the report from Windows Task Manager. The system was not jammed. But it became sluggish.

With 32 threads running, HotSpot Server 1.6.0_02 also took 99% of the CPU time according to the report from Windows Task Manager. But the system response time was much better that HotSpot client test.

With 128 threads running under HotSpot Client 1.6.0_02. The system became very sluggish. But I was able to launch other applications.

With 128 threads running under HotSpot Server 1.6.0_02. The system became sluggish. But everything is working fine.

With 512 threads running under HotSpot Server 1.6.0_02. The system became very sluggish. But the system was not totally frozen. I was still able to use a text editor to types these notes.

Obviously, there has been a major thread management improvement of JDK 1.6.0 on a Windows XP system over JDK 1.4.0 on a Windows 2000 system.

Another interesting observation was that JDK 1.6.0 took some time (about 5 minutes) to launch all 512 threads, see the timestamps recorded below. May be extra time was spend on requesting more memory from the Windows system.

10:24:08 PM Launched thread 1
10:24:08 PM Launched thread 2
10:24:08 PM Launched thread 3
10:24:08 PM Launched thread 4
...
10:28:32 PM Launched thread 489
10:28:32 PM Launched thread 490
10:28:32 PM Launched thread 491
10:28:32 PM Launched thread 492
10:28:32 PM Launched thread 493
10:28:41 PM Launched thread 494
10:28:41 PM Launched thread 495
10:28:41 PM Launched thread 496
10:28:50 PM Launched thread 497
10:28:50 PM Launched thread 498
10:28:50 PM Launched thread 499
10:28:50 PM Launched thread 500
10:28:50 PM Launched thread 501
10:28:59 PM Launched thread 502
10:28:59 PM Launched thread 503
10:28:59 PM Launched thread 504
10:28:59 PM Launched thread 505
10:28:59 PM Launched thread 506
10:28:59 PM Launched thread 507
10:28:59 PM Launched thread 508
10:28:59 PM Launched thread 509
10:28:59 PM Launched thread 510
10:28:59 PM Launched thread 511
10:28:59 PM Launched thread 512

Last update: 2007.

Table of Contents

 About This Book

 Download and Install Java SE 1.6 Update 2

 java.lang.Runtime Class - The JVM Instance

 java.lang.System Class - The Operating System

 ClassLoader Class - Class Loaders

 Class Class - Class Reflections

 Sun's JVM - Java HotSpot VM

 JRockit JVM 7.0 by BEA Systems

 JRockit JVM 8.0 by BEA Systems

 Memory Management Rules and Tests

 Garbage Collection Tests

 Stack Overflow Tests

Thread Testing Program and Result

 Thread Testing Program

Thread Testing Result with JDK 1.6.0

 StringBuffer Testing Program and Result

 CDS (Class Data Sharing)

 Micro Benchmark Runner and JVM Options

 Micro Benchmark Tests on "int" Operations

 Micro Benchmark Tests on "long" Operations

 Micro Benchmark Tests in JIT Compilation Mode

 Micro Benchmark Tests on "float" and "double" Operations

 References

 PDF Printing Version

Dr. Herong Yang, updated in 2010
Thread Testing Result with JDK 1.6.0