It happened to be Double Eleven some time ago. Usually before and after Double Eleven, there will be a small climax of part-time orders for Python. During this period, the demand for reptiles and data classification in various industries will increase dramatically! Many friends in the circle are busy during weekends, and many of them […]
Tag: der
HikariCP connection pool: Possibly consider using a shorter maxLifetime value.
Error analysis and positioning A database cluster is used in the project. When using it, it is found that the project is running and the database has not been operated for a period of time. If the database is operated again after a period of time, the following error will appear on the console. Failed […]
How does Nginx solve the thundering herd effect?
What is the thundering herd effect? When I first heard this term, I thought it was very interesting. I didn’t know what it meant. I always thought it was caused by the strange Chinese translation. Complex said (from the Internet) TLDR; The thundering herd effect refers to when multiple processes (multi-threads) are blocked and waiting […]
Call opencv library programming to display pictures and student ID names under Ubuntu
Article directory 1. Principle of Chinese character dot matrix font library (1), Chinese character encoding 1. Location code 2. Internal code (2) Dot matrix font structure 1. Bitmap font storage 2. 16*16 dot matrix font library 3. 1414 and 1212 dot matrix fonts (3). Acquisition of Chinese character lattice 1. Use location code to obtain […]
Call opencv library programming under Ubuntu to display a picture and display characters
? 1. Internal code, location code encoding rules and glyph data storage format of Chinese characters The in-machine code, location code encoding rules and glyph data storage format of Chinese characters are concepts related to Chinese character information processing. Here is a brief description: 1. Internal code: Internal code is the binary encoding used internally […]
Starting from single testing, improve the underlying API effect function in the Vue3 source code
Based on the effect method implemented in the previous article, based on the single test in the Vue3 source code, three functions of this method are improved, namely: runner: effect can return a self-executing parameter runner function scheduler: effect supports adding the scheduler function in the second parameter option stop: effect Adds stop function runner […]
Springboot java introduces Mqtt to receive and send messages under the framework of the front and back separation version
This is just one of them, and it is a superficial method of receiving and sending messages. The synchronization mechanism needs to be communicated and confirmed with colleagues engaged in the Internet of Things to see if it can be implemented. Or if there are many devices, the synchronization mechanism will not be used. First, […]
Understanding of arm bare metal lighting led volatile
1. Initialization process Initialize clock Set the multiplexed IO port of GPIO Set the electrical properties of GPIO Initialize GPIO 2. Understanding volatile initialization registers in C language #define CCM_CCGR0 *((volatile unsigned int *)0x020C4068) Understanding of volatile The volatile keyword has the following uses: (1) Used for synchronization, because the same thing may have multiple […]
STM32F103C8T6, use HAL library to simulate IIC reading MT6701 magnetic encoder
Foreword: The MT6701 magnetic encoder has a variety of reading methods, but the SSI and IIC reading methods are generally used more often. The blogger here uses the IIC driving method. The configuration of software and hardware is as follows, with source code attached, hoping to help more people. This article recommends two blogs: STM32 […]
threejs(13)-shader set point material
Shader material built-in variables The built-in variables of the three.js shader are gl_PointSize: In point rendering mode, controls the rendering pixel size of the square point area (note that this is the pixel size, not the three.js unit, so when the camera is moved, the size of the point seen on the screen remains unchanged) […]