Summarize the example usage tutorial of copy-on-write

Introduction to the problem First, let’s take a look at the assignment and reference issues in PHPWhat is your answer to the middle question? Before today, my answer was that memory space would be allocated for b. Because this is what I understand: When & is assigned, it is regarded as an alias defined for a variable, and a reference to the memory space is added. Changing one of them will affect the other references. When using unset(), the reference to the variable memory space is only disconnected, and the memory space will not be released. The = assignment is different. It will re-open a memory space to store a copy of the original variable. Modifications between the two will not affect each other. The following program confirms this point

1. Copy On Write code example sharing in PHP

#Introduction: Introduction to the problem First, let’s take a look at the assignment and reference issues in PHP. For the middle question, what is your answer? Before today, my answer was that memory space would be allocated for b. Because this is how I understand it: &Assignment

2. php Garbage collection mechanism----copy-on-write and reference counting

Introduction:: This article mainly introduces the PHP garbage collection mechanism - copy-on-write and reference counting. Students who are interested in PHP tutorials can refer to it.

3. Reference counter and copy-on-write of php variables

Introduction::This article mainly introduces Reference counters and copy-on-write of PHP variables, students who are interested in PHP tutorials can refer to it.

4. PHP underlying analysis: About copying cow cow’s plural winning color forum ww7349cow Japanese cow milk stone

Introduction: cow, php: PHP underlying analysis: About copy-on-write cow: data-id="1190000004926603"> If you want to reach the technical ceiling, Then the learning process lies in knowing what is happening and why. Today we will discuss the underlying copy-on-write (also called split-on-write) of PHP. First, let’s take a look at a piece of code: I believe everyone knows the output results of the two pieces of code, but today we will talk about what happened. The picture below is the structure of PHP storage variables (comments have been written for convenience of explanation), zend.h is in the Zend directory. It can be seen that the structure stores variable values, and several variables point to the

5. Strange phenomena during foreach traversal (PHP5)

Introduction: :Strange phenomena during foreach traversal (PHP5): data-id="1190000005044925" data-license="sa">Three major pitfalls in the basics of PHP, foreach traversal, reference mechanism &, array. Today we are talking about some strange phenomena in foreach. Before explaining, you can read my other related articles, which belong to the same big knowledge point. Reading them all will help your understanding. What exactly happens internally when we use foreach? (PHP5) PHP low-level analysis: About copy-on-write (cow) PHP low-level analysis: About force

6. Some difficult points in memory management of PHP principles_ PHP Tutorial

#Introduction: Several difficult points in memory management of PHP principles. PHP's memory management is divided into two parts. The first part is PHP's own memory management. The main content of this part is reference counting, copy-on-write, and other application-oriented management. And the third part

7. PHP source code analysis - variable reference counting, copy-on-write (Reference counting & Copy-on-Wr_PHP tutorial

Introduction: PHP source code analysis - variable reference counting, copy-on-write (Reference counting & Copy-on-Wr). There are two assignment methods in PHP syntax: reference assignment and non-reference assignment. ?php $ a = 1; $b = $a; // Non-reference assignment $c = $b; // Reference assignment?php $a = 1; $b = $a; // Non-reference assignment $c

##8. Understanding PHP reference counting and copy-on-write_PHP tutorial

##Introduction: Understand PHP reference counting and copy-on-write usage. Reference counting and copy-on-write (copy-on-write) are used to manage memory. Reference counting ensures that the memory is returned to the operating system when the reference is no longer needed, and copy-on-write ensures that the variable is copied between variables.

#9. Introduction to PHP Copy On Write_PHP Tutorial

Introduction: Introduction to PHP Copy On Write . Before we start, we can look at a simple code: Copy the code as follows: ?php //Example 1 $foo = 1; $bar = $foo; echo $foo + $bar; ? Execute this code, it will Print out the number

10. Introduction to copy on write copy on write mechanism in PHP_PHP tutorial

Introduction: Introduction to the copy on write mechanism in PHP. What is copy on write? Answer: When copying an object, the original object is not actually copied to another location in the memory. The content of the new object

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##How to understand the copy-on-write feature of PHP? #

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