Eighth ask Dubbo interview, which you can answer it right?

1. What Dubbo that?

2. What do Dubbo?

3. Dubbo built what kinds of services the container?

4. Dubbo core configuration What?

5. Dubbo What kinds of fault-tolerant cluster scheme, the default is what?

6. Dubbo, which has several load balancing strategy, the default is what?

7. Dubbo default what communications framework, there are other options?

8. Do you think good or good use of Dubbo SpringCloud?

What 1.Dubbo that?

Dubbo Alibaba open source high performance RPC-based distributed services framework for Java, has now become the Apache Foundation incubator project. We are committed to providing high performance and transparency of RPC remote service call programs, services and SOA governance program.

Simply put, dubbo is a service framework, if not distributed demand, in fact, we do not need, and only when distributed, have dubbo demand for such a distributed service framework, and is called a service essentially stuff, it means a distributed framework for remote service invocation (farewell Web service mode wSdl, to service providers and consumers Register on dubbo)

The core section includes:

1. Remote Communication: providing a variety of frame based NIO package length abstract connection model comprises a plurality of threads, serialization, and - information exchange "request-response" mode.

2. Fault-tolerant cluster: providing a transparent interface method is based on remote procedure calls, including multi-protocol support, as well as soft load balancing, fault tolerance failure, address routing, dynamic configuration and other cluster support.

3. Automatic discovery: a registry-based directory service, the service can only consume dynamic lookup service provider, the address is transparent, so that the service provider may increase or decrease smooth machine.

2. Dubbo what to do?

1. Transparent remote method invocation, the same as calling a local method call remote methods, only a simple configuration, without any intrusion API.

2. Soft load balancing and fault tolerance mechanisms, including the network can replace F5 hardware load balancer, lower costs, reduce single point.

3. Automatic registration and service discovery, no longer need to write the dead service provider address, IP address registry based query interface name service provider, and can be smoothly add or remove services provider.

Spring arrangement with full Dubbo, transparent access applications, application no intrusion API, the configuration can be simply loaded with Spring Dubbo, Dubbo Spring-loaded extension Schema.

3.Dubbo built what kinds of services the container?

Spring Container

Jetty Container

Log4j Container

4.Dubbo core configuration What?

Configuration relations:

5.Dubbo What kinds of fault-tolerant cluster scheme, the default is what?

6.Dubbo which has several load balancing strategy, the default is what?

7.Dubbo default what communications framework, there are other options?

Dubbo default Netty framework, and recommended choice, in addition to the content is also integrated Mina, Grizzly.

8. Do you think good or good use of Dubbo SpringCloud?

Not good or bad, just not suitable.

 

dubbo advantage

 

• A single application framework, when site traffic is small, only one application, all functions are deployed together to reduce costs and deploy nodes. In this case, for simplifying CRUD workload data access frame (ORM) is the key.

• Vertical application architecture, when traffic is gradually increasing, a single application to bring the machine to increase acceleration getting smaller and smaller, the application is split into several disparate applications to improve efficiency. In this case, a Web framework to accelerate the development of the front page (MVC) is the key.

• Distributed services architecture, when more and more vertical applications, the inevitable interaction between applications, will be drawn out of the core business, as an independent service, and gradually form a stable service center, the front-end applications to more quickly respond to changing market demand. In this case, for improving distributed service framework (RPC) service multiplexing and integration is the key.

• When the service flow computing architecture more and more, to assess the capacity of small service waste of resources and other issues is gradually emerging, this time a dispatch center based on the need to increase access to real-time pressure management cluster capacity, improve cluster utilization. In this case, used to improve scheduling and resource management center utilization of machines (SOA) is the key.

 

SpringCloud advantage

 

• Convention over configuration

• Out of the box, Quick Start

• For a variety of environments

• Lightweight components

• Component supports rich, full-featured

 

Comparison of the two

1, dubbo because it is binary transmission, bandwidth will be less

2, springCloud is http transmission protocol, the bandwidth will be more while using the http protocol typically use JSON messages, consumption will be greater

3, dubbo of development more difficult, because the jar package dependencies dubbo many large projects can not be solved

4, springcloud interface agreement relatively free and loose, requires strong administrative measures to restrict the interface disorderly upgrade

5, registry dubbo can choose a variety of zk, redis, etc., springcloud the registry can only be used eureka or self-study

According to the characteristics of the specific team level, and other business conditions, dubbo and SpringCloud each can play different advantages, not the best framework, only the most suitable. (This question is more flexible, and if the other party know in advance which company uses, which can blow hard ~)

 

Recently three

[23] you tell us about the IO synchronous, asynchronous, blocking, non-blocking difference

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[25] This three common interview questions, you have been asked before?