Go 1.16 contains many Modules-related updates, and you can directly view its Release Note for details. Overall, it contains the following points: Go111module is On by default. If you want to restore the previous behavior, you need to set Go111module to Auto, which almost means that the GOPATH mode will gradually fade out of people’s vision; The go… Read More »
Background Pika is a persistent large-capacity redis storage service, compatible with most of the interfaces of string, hash, list, zset, and set (compatibility details), and solves the capacity bottleneck of redis that is insufficient due to the huge amount of stored data. Users can migrate from redis to pika service without modifying any code. It has good compatibility… Read More »
SOLID principle introduction Following practical and clear design principles is conducive to flexible and reliable software design. SOLID is an acronym for the five essential principles of object-oriented design. When we design classes and modules, following the SOLID principles can make the software more robust and stable. Q1: What are the SOLID principles? S – Single responsibility principle… Read More »
What is CSRF? CSRF is an abbreviation of Cross-Site Request Forgery. It is a script that can send HTTP requests. The victim can be disguised to send a request to the website to achieve the purpose of modifying the website data. CSRF can steal all user cookies after the user clicks a link so that the account is… Read More »
Introduction R2DBC is an asynchronous, non-blocking relational database connection specification. Although some NoSQL database vendors provide reactive database clients for their databases, for most projects, migrating to NoSQL is not an ideal choice. This prompted the birth of a universal, responsive relational database connection specification. As a relational database with a huge user base, MySQL also has a… Read More »
Introduction One-to-many results paging is a prevalent scenario, for example, we want to query the product and product picture information. But many people will encounter the misunderstanding of paging here and get incorrect results. Come to analyze and solve this problem today. Problem analysis Let’s first create a simple commodity table and the corresponding commodity picture relationship table.… Read More »
Idempotency Idempotency means that no matter how many times you execute the request, the result is the same. Speaking of idempotency, you have to say repeated submission. You click the submit button continuously. In theory, this is the same piece of data. The database should only store one item but store multiple items, which violates idempotency. Therefore, we… Read More »
Why do we use scheduled tasks For the static homepage, considering that the data of the page may be maintained by multiple operating personnel and changes frequently, it is made into a scheduled task, that is, the static is performed regularly Performing scheduled tasks in Django can be achieved through the django-crontab extension. Installation Configure installed applications Add… Read More »
Queue-based and message-based TTL TTL is short for time to live, as the name implies refers to the time to live of the message. rabbitMq can set the message expiration time from two dimensions, namely the queue and the message itself.Queue message expiration time-Per-Queue Message TTL:Set the x-message-ttl parameter of the queue to set the message’s survival time… Read More »
In virtual paging storage, the virtual storage space and physical main storage space are divided into pages of fixed size, and the memory allocation for threads is also in units of pages. For example, if the page size is 4K, 4GB/4KB=1M records are needed for 4GB storage space, that is, there are more than 1 million 4KB pages.… Read More »
Redis brief introduction Redis is a key-value database written in c language, open-source, and highly available non-relational database (NoSQL, not just database) type. Unlike traditional databases, Redis data exists in memory, so the read and write performance is not generally high, and can reach 100,000 operations per second, so it is widely used in the cache direction, for… Read More »
Have you ever been in a situation like this? Use the SSH command to enter the server, use the CD command to enter the corresponding directory, and continue your work. This is especially common for novices. In this article, the veteran driver will take you to a more efficient operation, just one step to achieve the desired results.… Read More »
Questions: Describe the Java garbage collection mechanism. What is GC? Why do we use GC? Advantages and principles of garbage collection, and describe two recovery mechanisms. What is the basic principle of the garbage collector? Can the garbage collector reclaim memory immediately? What’s the way to actively notify the virtual machine for garbage collection? What are the reference… Read More »
Heap Java’s heap is a runtime data area, and objects of classes allocate space from the heap. These objects are created by instructions such as new and destroyed by the garbage collector. The advantage of the heap is that it can allocate memory space dynamically. It is unnecessary to tell the compiler how much memory space is needed… Read More »
We can create a simple heartbeat animation using HTML and CSS without much coding. The only thing we need to do is to add a box and use CSS to display it. First, add a visual box to the page Then, make a heart-shape box Finally, set up the animation. It’s worth noticing that the animation must be… Read More »
When configuring the server, it is often necessary to check whether the server port is open. If there are only one or two servers, this is easy to do, use the nc command to view them one by one. However, if your server is in a cluster, then there are many ports to be checked? If you still… Read More »
It is rumored that fasthttp is faster than Nginx in some scenarios, indicating that fasthttp should be optimized. Let’s do some benchmark performance tests. The first test to run is a simple hello server benchmarking. The following results are obtained on Mac. There may be differences under Linux. fasthttp Nginx with standard modules Nginx with rust actix and… Read More »
Client-side architecture The Client class has only one entry, which is the call() method. The proxy class will call the Client.call() method to send the RPC request to the remote server, and then wait for the response from the remote server. If an exception occurs when the remote server responds to the request, an exception is thrown in… Read More »
When we make a decision every day, we often consult several people and comprehensively adopt their opinions. So is it possible to copy this idea into the field of machine learning and create multiple models to synthesize the results? Synthesizing is, of course, viable, and this idea is called the ensemble method. Ensemble method The ensemble method itself… Read More »
The evaluation strategy of a compiler is usually divided into pass-by-call and pass-by-call. Thunk functions are implemented by pass-by-call by the compiler. They often put parameters into a temporary function and then put This temporary function is passed into the function body. This temporary function is called the Thunk function. Evaluation strategy Compiler evaluation strategies are usually divided… Read More »