方法区是JVM的规范，永久代(持久代)是JVM规范的一种实现只有HotSpot JVM有HotSpot JVM，对于其他类型的虚拟机例如J9(IBM)、JRockit(Oracle)都没有方法区是连续的堆空间，当加载的类信息容量超过了最大可分配空间，会引发OutOfMemoryError错误，永久代(持久代)的GC与老年代捆绑，只要其中一个
We learned about Java memory model and its memory area and structuring inside JVM. We will come up with ideas to use this information for performance tuning in the coming posts. Happy Learning !! Reference:http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-2.html...
Java内存模型(JMM)我们常说的JVM内存模式指的是JVM的内存分区;而Java内存模式是一种虚拟机规范。 Java虚拟机规范中定义了Java内存模型(Java Memory Model,JMM),用于屏蔽掉各种硬件和操作系统的内存访问差异…
Oracle Java ME Embedded is a Java runtime that leverages the core Java ME technologies deployed in billions of devices around the world in the Internet of Things. The Java ME specifications are designed to be rich in functionality, portable to a wide range of devices, flexible, and secure wh...
绝大部分Java程序员应该都见过“java.lang.OutOfMemoryError: PremGen space”异常。这里的“PermGen space”其实指的就是方法区。不过方法区和“PermGen space”又有着本质的区别。前者是JVM的规范,而后者则是JVM规范的一种实现,并且只有HotSpot才有“PermGen space”,而对于其他类型的虚拟机,如JRockit(Oracle)、J9...
Young and Old generation space. It divides the heap space into multiple equal-sized heap regions. When a garbage collection is invoked, it first collects the region with lesser live data, hence “Garbage First”. You can find more details about it atGarbage-First Collector Oracle Documentation....
Young and Old generation space. It divides the heap space into multiple equal-sized heap regions. When a garbage collection is invoked, it first collects the region with lesser live data, hence “Garbage First”. You can find more details about it atGarbage-First Collector Oracle Documentation....
The Java Memory Model https://docs.oracle.com/javase/specs/jls/se9/html/jls-17.html#jls-17.4 http://www.infoq.com/cn/articles/java-memory-model-1 http://gee.cs.oswego.edu/dl/jmm/cookbook.html http://www.cs.umd.edu/~pugh/java/memoryModel/jsr133.pdf ...
内存模型的英文是memory model,或者更精确的来说是memory consistency model,它其实就是一套方法或规则,用于描述如何在多核乱序的情况下,通过一定的方式,来保证指定代码的有序执行。 它是介于硬件和软件之间,以一种协议的形式存在的。 对硬件来说,它描述的是硬件对外的行为规范,对软件来说,它描述的是编写多线程代...
Oracle Java ME Embedded is a Java runtime that leverages the core Java ME technologies deployed in billions of devices around the world in the Internet of Things. The Java ME specifications are designed to be rich in functionality, portable to a wide range of devices, flexible, and secure wh...