What is the default garbage collector for Java 8?

When I check the JMX Beans, they reveal it to be the parallel collector for the new generation and the old serial collector for the old generation.

解决方案

Selecting the default garbage collector (among other things) is what's called the ergonomics process of the JVM. This process depends on the class of your machine.

For server-class machine, defined as a machine with 2 or more physical processors and 2 or more GB of physical memory (regardless of the platform), the default garbage collector is the parallel collector (also known as throughput collector).

For client-class machine, defined as a 32-bit platform on Windows or a single-processor machine, the default garbage collector is the serial collector.

Since practically all machines have 2 or more CPU, a machine is practically always considered server-class by the JVM. That's why you will find a lot of references considering the parallel collector to be the default garbage collector.