Performance Enhancements - JDK 5 Documentation v1.2.2, Java 2 SDK 英文文档

Performance Enhancements

Solaris Native Thread Support
In a multi-processor environment, the Solaris kernel can schedule native threads on the parallel processors for increased performance. The native threads VM integrates better with native code than the default green threads VM. The VM can avoid some inefficient remapping of I/O system calls that are otherwise necessary.
Reduced Memory Usage for Loaded Classes
Constant strings are shared among different classes, resulting in reduced memory consumption for Java applications.
Faster Memory Allocation and Garbage Collection
The thread-local heap cache eliminates the need of locking for majority of heap allocations. Memory allocation speed is drastically increased. Garbage collection pauses are shorter. The garbage collector no longer excessively consumes the C stack.
Monitor Speedups
The thread-local monitor cache enables synchronized methods to run closer to the speed of normal methods.
Native Library JNI Port
Native libraries supporting core Java classes (e.g., AWT) have been rewritten using the Java Native Interface (JNI). The resulting code is more efficient and can run unmodified on different Java Virtual Machines.
Just In Time (JIT) Compilers
JIT compilers are being included with the Java^® 2 SDK and Java 2 Runtime Environment.