Difference Between Primordial and Non Primordial Thread

Question

In Open JDK note I found this precise comment

Creates the VM using JNI_CreateJavaVM in a newly created thread (non primordial thread). Note: creating the VM in the primordial thread greatly reduces the ability to customize the VM, for example the stack size on Windows, and many other limitations

Could not find much literature on this in google !! :O. Please enlighten.

Answer 1

When a new process is started by the operating system, only a single thread exists. This is the thread which will enter the native main function of the application which then may start more threads. This initial single thread is the “primordial thread”; it doesn’t seem to be a formal term but rather a phrase which meaning should be derived from context.

It’s comprehensible that a newly created thread can be customized easier than a thread already existing on process start.

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Addition: I found a blog entry explaining the issue of your question. Thankfully, its first sentence gives the definition for the rest of the blog entry:

A primordial thread is the first thread created by the Operating System kernel when a process is created.