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Redis is an advanced key value database. The data is stored in memory. Fast speed is an advantage, but the data changes rapidly. How to save the data? This is the redis persistence mechanism summarized today. What is persistence? Normal redis data is stored in memory. In case of a redis outage or restart, the data will be lost. Therefore, it ...

Distributed things thing: To ensure the ACID of data in a database We need to do things. In a database, multiple sql statements are either executed or not executed There are many conditions, including item isolation level Distributed things The current architectures are all distributed architectures. In order to ensure that multiple d ...

official Official website File download 1. Introduction to Zookeeper ZooKeeper is a distributed, distributed application coordination service. It is a software that provides consistency services for distributed applications. ( Source: Baidu Encyclopedia) Zookeeper features A cluster composed of one Leader and multiple followers;As ...

1. Component dependency First of all, we will introduce Jedis open source components through Maven, which can be found in POM. Com Add the following code to the XML file: <dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> <version>2.9.0</version> </depe ...

1. Document summary Source address: https://github.com/apache/rocketmq Chinese documents: https://github.com/apache/rocketmq/tree/master/docs/cn Commercial edition: https://www.aliyun.com/product/rocketmq Official website translation: http://www.itmuch.com/books/rocketmq/ FAQ: http://rocketmq.apache.org/docs/faq/ RocketMQ common managemen ...

Relationship of each node: The Invoker here is an abstraction of the callable Service of the Provider. The Invoker encapsulates the Provider address and Service interface information; Directory represents multiple invokers and can be regarded as a List. However, unlike List, its value may change dynamically, such as pushing changes by the reg ...

JanusGraph - generation strategy of distributed id Hello, I'm Yang Zi, JanusGraph graphic series articles, updated in real time~ Figure general directory of database articles: To sort out all articles related to graphs, please move (hyperlink): Figure database series - General Catalog of articles Address: https://liyangyang.blog.csdn.net/art ...

1, Quartz Cluster architecture Quartz is the most famous open source task scheduling tool in the Java field. In the previous article, we introduced the single application practice of Quartz in detail. If it is only applied in a single environment, Quartz may not be the best choice. For example, Spring Scheduled can also realize task schedulin ...

1, Random method Completely random: randomly select one of the servers for access according to the list size value of the back-end server through the random algorithm of the system. According to the theory of probability and statistics, as the number of calls from the client to the server increases, the actual effect is closer and closer to th ...

RPC call: the client serializes and transmits the service call interface, method name, method type parameters and method parameter values to the server, and the server reads the information in reverse sequence for proxy call. Summary: (1) When the client starts, it will pull and subscribe to the corresponding service list from the registry, and ...