CODING PUSH

  Cloud computing is a model for delivering information technology services over the internet. Instead of having software and hardware installed locally on a user's device, cloud computing allows users to access applications and data through a network of remote servers, usually maintained by a third-party provider . This provider is responsible for managing and maintaining the infrastructure, including servers, storage, databases, and software . Here is a more detailed explanation of how cloud computing works: Remote servers: Cloud computing relies on a network of remote servers that are maintained and managed by a third-party provider . These servers can be physically located anywhere in the world. Internet connectivity: To access cloud computing services, users must have an internet connection. This connection allows them to remotely access the resources on the remote servers. Virtualization: Cloud providers use virtualization technology to create multiple virtual machines ...

 

  Redis interview questions 1.What is Redis?. 2. What is the data type of Redis? 3. What are the benefits of using Redis? 4. What are the advantages of Redis over Memcached? 5. What are the differences between Memcache and Redis? 6. Is Redis single-process and single-threaded? 7. What is the maximum storage capacity of a string type value? 8. What is the persistence mechanism of Redis? Their advantages and disadvantages? 9. Redis common performance problems and solutions: 10. What is the deletion strategy of redis expired keys? 11. Redis recycling strategy (elimination strategy)? 12. Why does edis need to put all data in memory? 13. Do you understand the synchronization mechanism of Redis? 14. What are the benefits of Pipeline? Why use pipeline? 15. Have you used Redis cluster? What is the principle of cluster? 16. Under what circumstances will the Redis cluster solution cause the entire cluster to be unavailable? 17. What are the Java clients supp...

  Latest and most comprehensive big data/artificial intelligence terms & terminology in English (highly recommended for collection) for years 2021 and 2022   A  1.  Apache Kafka:  named after the Czech writer Kafka, used to build real-time data pipelines and streaming media applications. The reason it is so popular is that it can store, manage, and process data streams in a fault-tolerant manner, and it is said to be very "fast". Given that the social network environment involves a lot of data stream processing, Kafka is currently very popular.

Introduction to Cloud Computing Cloud computing is an emerging Internet-based business computing model. It distributes computing tasks on a resource pool composed of a large number of computers, enabling various application systems to obtain computing power, storage space and various software services as needed. Cloud computing is the development of parallel computing, distributed computing and grid computing, or the commercial realization of these computer science concepts.

 Data product managers and data analysts are currently popular positions in Internet companies. Their responsibilities overlap with those of data analysts. The difference is that this position focuses on the productization of data analysis. 

How to ensure the high availability of the message queue? Analysis of Interview Questions If someone asks about your MQ knowledge, high availability is a must . It’s good to ask this question, because I can’t ask you how to ensure the high availability of Kafka? How to ensure the high availability of ActiveMQ? If an interviewer asks this question, it seems very incompetent. People may use RabbitMQ. If you haven't used Kafka before, you come up and ask them what Kafka is doing? Isn't this just making things difficult? So a competent interviewer asks how to ensure the high availability of MQ? In this way, which MQ you have used, you can talk about your understanding of the high availability of that MQ.

 What are the differences between react and vue?  Similarities between react and vue ·  Both support server-side rendering All  have Virtual DOM, component development, pass the parent and child component data through props parameters, and all implement the webComponent specification ·  Data Driven View ·  Have native support for the program, React's React native, Vue's weex   Differences between react and vue   ·  React strictly only for the MVC view layer, Vue is the MVVM pattern The  virtual DOM is different. Vue will track the dependencies of each component and does not need to re-render the entire component tree. For React, every time the state of the application is changed, all components will be re-rendered, so it will be required in React. shouldComponentUpdate is a life cycle function method to control The  component writing method is different. The recommended method of React is JSX + inline style, whic...

 What are concept of physical address, logical address, and virtual memory in Java ? 1. Physical address: It is the final address of the address conversion. When the process executes instructions and accesses data when it is running, it must be accessed from the main memory through the physical address. It is the real address of the memory unit. 2. Logical address: refers to the address seen by computer users. For example: when creating an integer array with a length of 100, the operating system returns a logically continuous space: the pointer points to the memory address of the first element of the array. Since the size of the integer element is 4 bytes, the address of the second element is the starting address plus 4, and so on. In fact, the logical address is not necessarily the real address where the element is stored, that is, the physical address of the array element (the location in the memory bar). It is not continuous, but the operating system maps the logical address int...

 What is a deadlock? Deadlock refers to a stalemate caused by multiple processes competing for resources during operation. When the processes are in this stalemate, if there is no external force, they will not be able to move forward.   The reason for the deadlock? Because there are some inalienable resources in the system, and when two or more processes occupy their own resources and request each other's resources, each process will not be able to move forward, which is a deadlock.  A.  Competing resources For example: there is only one printer in the system that can be used by process A. Assuming that A has occupied the printer, if B continues to request the printer to print, it will be blocked.  The resources in the system can be divided into two categories: Deprivable resources: After a process obtains such resources, the resources can be deprived by other processes or systems. Both CPU and main memory are deprived resources; Inalienable reso...

 What are the different states of the process?  In the five-state model, there are 5 states in the process, which are created, ready, running, terminated, and blocked. The running state is that the process is running on the CPU. In a single-processor environment, at most one process is running at any time. The ready state means that the process is ready to run, that is, the process has obtained all the required resources except the CPU, and can run once it obtains the CPU. The blocking state is when the process is waiting for an event to suspend operation, such as waiting for a resource to be available or waiting for I/O to complete. Even if the CPU is idle, the process cannot run. Running state → blocking state: It is often caused by waiting for peripherals, waiting for resource allocation such as main memory, or waiting for manual intervention. Blocking state → Ready state: The waiting condition has been met, and it can run only after being allocated to the pro...

 What is the difference between concurrency and parallelism? Concurrency means that multiple tasks will be processed within a period of time; but at a certain moment, only one task is executing. Single-core processors can achieve concurrency. For example, there are two processes A and B. After A runs for a time slice, it switches to B, and B runs for a time slice and then switches to A. Because the switching speed is fast enough, the macroscopically shows that multiple programs can be run at the same time within a period of time. Parallel means that there are multiple tasks being executed at the same time. This requires a multi-core processor to complete, and multiple instructions can be executed at the same time at the microscopic level. Different programs are run on different processors. This is a physical process of multiple processes at the same time.   What is the difference between a large kernel and a micro kernel? The big kernel is to put all the functions of...

 What is a process? A process is a program being executed and is the basic unit of operating system resource allocation. Generally speaking, a process contains instructions, data, and PCB.   What is the difference between an orphan process and a zombie process? Orphan process means that a parent process exits while one or more of its child processes are still running, then these child processes will become orphan processes. The orphan process will be adopted by the init process (process with process ID 1), and the init process will complete the state collection work for them. Because the orphan process will be adopted by the init process, the orphan process will not cause harm to the system. A zombie process is a process descriptor of a child process that will not be released when the child process exits. It will only be released when the parent process obtains the child process information through wait() or waitpid(). If the child process exits and the parent proces...

 Today we will answer 3 questions  What is a cookie and what is the process of using a cookie? What is a session, and what mechanisms are there to implement a session? What is the difference between session and cookie?

 The difference between HTTP and HTTPS The main difference between HTTP and HTTPS is that the HTTP protocol transmits plain text data, while HTTPS transmits encrypted data, which means that HTTPS is more secure. It is also required by HTTPS to ensure security, so its performance is a bit worse than HTTP.   Security alone is not enough. I intend to expand on how HTTPS solves security problems. There is no mechanism through this HTTPs, which reflects the difference between HTTPS and HTTP. Let us try to derive the process of HTTPS encryption. 

When it comes to SEO, most people will quickly think of the construction of external links, which play a vital role in website weight and inclusion. So, what are the forms of external links? There are many different forms of external links. I will share with you the different forms of external links commonly used by website SEO personnel for optimization.  Image by fancycrave1 from Pixabay

Website design is both simple and difficult. A good web design will greatly enhance the user experience of the website. Web design is simple, but it is not that simple to do. What are the tips for effective web design? 

 What is the purpose of the command interpreter? Why is it usually separate from the kernel? Would it be possible for the user to develop a new command interpreter using the system‐call interface provided by the operating system? Answer: It reads commands from the user or a file of commands and executes them, usually by turning them into one or more system calls. It is usually not part of the kernel since the command interpreter is subject to changes. A user should be able to develop a new command interpreter using the system‐call interface provided by the operating system. The command interpreter allows a user to create and manage processes and also determine ways by which they communicate (such as through pipes and files). As all of this functionality could be accessed by a user‐level program using the system calls, it should be possible for the user to develop a new command‐line interpreter. Why is the separation of mechanism and policy desirable in an operating system? Answer:...

  What is Lock splitting technique? Lock splitting is a technique to reduce Lock contention in multithreading.  It is applicable in scenario when one lock is used to synchronize access to different aspects of the same application. Sometimes we put one lock to protect the whole array. There can be multiple threads trying to get the lock for same array.  This single lock on array can cause Lock contention among threads.  To resolve this we can give one lock to each element of the array. Or we can use modulus function to assign different locks to a small group of array elements.  In this way we can reduced the chance of Lock contention. This is Lock splitting technique. Which technique is used in ReadWriteLock class for reducing Lock contention? ReadWriteLock uses two locks. One lock for read-only operations, another lock for write operations. Its implementation is based on the premise that concurrent threads do not need a lock when they want to read a value while ...