BackgroundBefore getting into the main content, let me give a brief introduction to WaitGroup and its related background knowledge. Here, the focus is on the basic usage of WaitGroup and the fundamental knowledge of system semaphores. For those who are familiar with these, you can skip this section directly.WaitGroupWaitGroup is one of the most common concurrency control techniques in Golang, and its function can be roughly compared to the join() in concurrency control of other languages' multithreading. The sample code is as follows:package mainimport ( "fmt" "sync" "time")func main(...

Etcd, one of the crucial components of Kubernetes. If APIServer is the heart, then etcd is the blood vessel that sends the end state of Kubernetes resources to various “organs”, providing high-speed, stable storage, and supporting APIServer’s high load performance. What if the etcd is not working properly? Just the condition as someone has a vascular disease. The deeper you know about them, the better diagnose you can make when issues occur.from unsplash, @John BarkipleRemember the local cache we finished in 20 minutes? If that is a short st...

Java 8 was recently released, many developers are now trying to extract the source code of Java 8 to find out how the new added features such as Lambda expressions, default method in interfaces, new Time API are implemented. How do you manage to download and browse the source code? Today we are going to show how to extract OpenJDK Java source code to Eclipse.Since OpenJDK is adopting Mercurial as its distributed version control system, you need to install Mercurial on your computer first before you can clone the repository from OpenJDK. You can get more info about the use of Mercurial in OpenJ...