1. Purpose of the experiment
Understand HDFS architecture and working principle Master HDFS deployment environment and steps Master HDFS (cluster startup start-dfs.sh) startup Use Hadoop commands (file addition/deletion/modification/check/upload/download) to operate the distributed file system
2. Experimental content
HDFS pseudo-distrib ...
Posted by gaspower on Sat, 31 Dec 2022 06:51:29 +0300
Execute IO events
As mentioned above, the user's message records are converted into memory records and stored in the flight window, and the request information is put into the Kafka channel and passed through
OP_WRITE event to wake up IO, where IO logic is started in IO rotation training
The core logic of calling the poll method of Netw ...
Posted by Atanu on Mon, 14 Nov 2022 22:02:12 +0300
For commercial reproduction, please contact the author for authorization. For non-commercial reproduction, please indicate the source.For commercial use, please contact the author for authorization. For non-commercial use, please indicate the source.License: signature - non-commercial use - sharing in the same way 4.0 International (CC BY-NC-SA ...
Posted by avillanu on Thu, 01 Sep 2022 23:07:53 +0300
Leaf is a distributed ID generation service launched by meituan. Its name is taken from the words of German philosopher and mathematician Leibniz: "there are no two identity leaves in the world." ("there are no two same leaves in the world"), taking a name has such moral meaning, meituan programmer Niu break!
Posted by Chris_Evans on Wed, 25 May 2022 07:06:18 +0300
hystrix is a well-known service degradation and fusing component launched by Netflix
The main principle of hystrix design is to solve the cascading failure of associated services caused by network uncertainty in distributed environment.
For example, service A calls service B, service B calls Service C, and Service C calls service D. d ...
Posted by inerte on Tue, 24 May 2022 18:30:07 +0300
Original address: RocketMQ sample - always on the way
1 basic example
In the basic example, we provide the following function scenarios:
Use RocketMQ to send three types of messages: synchronous message, asynchronous message and one-way message. The first two messages are reliable because there will be a response whether the transmission is s ...
Posted by joebarker99 on Mon, 23 May 2022 17:27:34 +0300
In most cases, we usually use quartz open source framework to meet the application scenarios for scheduled tasks. However, if you consider other factors such as robustness, you need to make some efforts. For example, to avoid a single point of failure, you have to deploy at least two nodes. However, deploying multiple nodes has other problems. ...
Posted by fotakis on Sun, 22 May 2022 14:35:57 +0300
1. Message format of JMS
JMS message consists of the following three parts:
Each header field has corresponding getter and setter methods.
If you need a value other than the header field, you can use the message properties.
The message types defined by JMS include TextMes ...
Posted by faizanno1 on Sat, 21 May 2022 23:41:37 +0300
1, Definition of SOA and DDD
SOA and DDD are common system architectures, but the core of them is different.
SOA (service-Oriented Architecture) was proposed by Gartner in 1996. It is a distributed software architecture. It can deploy, combine and use loosely coupled coarse-grained application components through the network according to requi ...
Posted by marcela1637 on Wed, 18 May 2022 13:32:18 +0300
Error problem display
This problem bothered me all day. I don't know why. Fortunately, there are big guys on the Internet. The reference blog is at the bottom.
When dubbo is used to transfer MultipartFile files, an invoke method error will be reported because dubbo cannot transfer this object across the system. Hessian can be ...
Posted by willpower on Wed, 18 May 2022 11:38:29 +0300