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catalogue concept Four concepts Producer Switch Queue Consumer Six modes working principle Download Installation Docker installing RabbitMQ concept Rabbit is a message oriented middleware that can accept and forward messages. You can regard it as an express site. When you want to send a package, you put your package in the expre ...

preface First of all, it is clear that method parameters in Java are passed by value. For basic types (int a, long b), values are passed when parameters are passed. For example, if int a = 5, 5 is passed. If it is a reference type, pass the address value pointing to the memory address of the specific object, such as system out. Println (New ob ...

requirement analysis At present, the company has launched the push interface of express 100. Now it needs to make an interface for the estimated arrival time of express. This interface is mainly used for month end assessment of signing in and warehouse personnel. For example, an express signed in on the 15th, but only entered the warehouse on ...

1, Foreword Redisson distributed interlocking RedissonMultiLock objects based on Redis can associate multiple RLock objects into an interlocking, and each RLock object instance can come from different redisson instances. Of course, this is the introduction of the official website. What is it? Let's take a look at the use and source code of int ...

Publisher confirmation Publisher confirms(using the java client) Publisher validation is an extension of rabbitMQ for reliable publishing. When publisher acknowledgement is enabled on the channel, messages published by the client will be asynchronously acknowledged by the agent, which means that they will be processed by the server. ...

Logging, Metrics and Tracing relationships Same: to improve the observability of infrastructure and Applications Difference: ----LoggingMetricsTracingCharacteristicRecord discrete eventsRecord aggregable dataRecord information within the scope of the requestTypical IndicatorsUser-printed debugging information...QPS, Interface Delay Distribut ...

preface In distributed systems, registry plays an important role and is an indispensable member of service discovery and client load balancing. In addition to the basic functions of the registry, its stability, availability and robustness have a significant impact on the smooth operation of the whole distributed system. As a mainstream distrib ...

origin At present, most companies are distributed services. For the analysis of production logs, a log collection system needs to be built to facilitate development, operation and maintenance to analyze and monitor production problems. This blog uses filebeat + Kafka + logstash + elastic search + kibana to build a distributed log collectio ...

Redis advanced features Slow query Many storage systems (such as MySQL) provide slow query logs to help developers and operation and maintenance personnel locate the slow operation of the system. The so-called slow query log is that the system calculates the execution time of each command before and after the command is executed. When it exce ...

By default, Spark can divide a job into multiple tasks and send it to the Executor node for parallel computing. The number of tasks that can be calculated in parallel is called parallelism. This number can be specified when building the RDD. However, the number of splitting tasks is not necessarily equal to the number of tasks executed in paral ...