What is a thread? What does the thread of the CPU mean

What exactly is a thread? As shown in Figure A, a thread is a sequence of given instructions (the ones you wrote), a stack (the variables defined in a given method), and some shared data (variables at the class level). Threads can also access static data from global classes.

stack and possibly some shared data.

Each thread has its own stack and program counter (PC). You can think of a program counter (PC) as keeping track of instructions that a thread is executing, and stacks for tracking the context of a thread, which is the value of the current local variable when the thread executes somewhere. While you can write subroutines that transfer data between programs, under normal circumstances, one thread cannot access the stack variables of another thread.

A thread must be in one of four possible states:

Initial state: The state in which a thread is in after the new method is called, and before the start method is called. In the initial state, the start and stop methods can be called.

runnable: Once the thread calls the start method, the thread goes to the runnable state, note that if the thread is in the runnable state, it may not be running, due to priority and scheduling issues. Blocking nonrunnable:

The thread is in a nonrunnable state, which is caused by two possibilities: either it is paused due to a hang, or it is blocked for some reason, such as including waiting for the completion of an IO request. Exit:

There are two possibilities for a thread to go to an exit state, either the run method has ended or the stop method has been called.

The last concept is thread priority, threads can be prioritized, and high-priority threads can be scheduled to finish before low-priority threads. An application can set the priority size of a thread by using the method setpriority(int) in the thread.

Threads are the smallest unit of CPU scheduling, and one process is created when a program system is executed, but this process can have multiple threads.

It refers to a single process task during the running of a program, you can create multiple threads in a program at the same time, and they can run in parallel without interfering with each other.

If a problem occurs on one of the threads, it will not affect the other processes. This ensures the robustness of the program!

A thread is the smallest unit in which an operating system can schedule operations. It is contained in the process and is the actual operating unit of the process.

A thread refers to a single-order control flow in a process in which multiple threads can be concurrent, each performing a different task in parallel.

Also known as lightweight processes in Unix System V and Sunos, lightweight processes refer more to kernel threads and user threads to threads.

A process can have many threads, each performing a different task in parallel.

The benefits of using multi-threaded programming on multi-core or multi-CPU, or CPUs that support Hyper-Threading, are obvious, i.e., increased execution throughput.

On a single-CPU and single-core computer, using multi-threading technology, the part that is often blocked in the process and the part that is responsible for IO processing and human-computer interaction can also be separated from the part of intensive calculation, and a special workhorse thread can be written to perform intensive calculation, so as to improve the execution efficiency of the program.

First of all, let's take an example: the rendering pipeline in the GPU is similar, the pipeline will process a large number of graphics rendering, and each pipeline can process tasks in parallel at the same time.

CPU threads are similar to GPU pipelines, with each thread processing multiple programs. Multi-core CPU is also multi-threaded, as long as the program supports multi-core processing, the program can use multi-threading to process and speed up the program execution efficiency. It's like 1 pickup truck and 1 big truck delivering goods.

Although the speed of the two vehicles is the same, the lack of goods transported is twice as large. On the other hand, if an executor is divided into two parts of parallel operation, its operation time should be reduced.

There are currently two types of CPU threads, one thread per core and two threads per core. According to Intel's theory, a CPU that supports two threads is more efficient than a single thread.

A CPU has two threads, which is a double thread. It is to virtualize a single-core CPU into a dual-core, a dual-core virtual into a quad-core, and so on. Double double, commonly known as double threading.

A thread refers to a sequence of instructions to be executed by a program, and the Win32 platform supports multi-threaded programs, allowing multiple threads to exist in a program. In a single-CPU system, the system allocates the CPU's time slices to each thread according to the scheduling algorithm, so each thread is actually executed time-sharing, and in a multi-CPU Windows NT system, different threads of the same program can be assigned to different CPUs for execution.

Hyper-threading technology is used when there are two cores in the processor, one core has 2 threads, so two cores have 4 threads. The number of CPUs seen in the operating system is twice as large as the actual number of physical CPUs, that is, 1 CPU can see two, and two can see four.