Design e-commerce seckill system

【 background 】 

【 Business background 】 

As an architect of an e-commerce startup , Responsible for the design 6.18 Design of big promotion second kill system , Your business model is as follows ：

 1.  You choose the best-selling and highly praised products on major e-commerce platforms to sell , No more than... Per category 20 A commodity , At present, we have done 10 Categories ; 

2.  This time 6.18 Second kill chose 1000 A power bank ,10 platform  iPhone 12  As a second kill commodity ;

 3.  The normal daily life is about 100 Million users ; 4.  The boss asked to be foolproof . 

【 Technical background 】 

1.  The technical team takes  Java  Mainly , The microservice architecture has been implemented ; 

2.  The main channels are self owned  App（ Include  iOS  and  Android） And WeChat applet , In order to promote the transformation of users into  App  user , Download only  App  To participate in the second kill ; 

3.  At present, there are only single rooms . 

【 Completion requirements 】 

1.  Design a complete architecture , Such as storage 、 Load balancing 、 cache 、 High availability 、 Expandable etc ; 

2.  about 10 Within the page  PPT, each page  PPT  Explain a design , Including architecture design and design reasons , There is no need to explain the alternatives in detail . 

【 Tips 】 

1.  Analysis and consideration should be comprehensive , But it doesn't mean that the architecture design should be comprehensive , If it is considered that some design points can not be done after analysis , Explain the reasons uniformly at the end of the operation ; 

2.  If there is no thought , Please refer to the module 9 Of  IM  Case study ; 

3.  If some information is not complete or detailed enough , You can make certain assumptions , But you can't fly in the sky , It is necessary to make a reasonable inference against the existing business background and technical background

【 Basic business scenarios 】

1. Users can browse products at will

2. Users only have APP Log in to place an order for seckill products

3. The second kill commodity cannot be killed before it is started

4. Users can only buy one of each commodity category

5. Seckill success , Generate order , Inventory deduction , Waiting to be paid

6. Payment call   Third party service ,

7. Successful payment , Change order status

8. Failure to pay , Payment timeout , Order cancellation , Inventory recovery

【 The overall structure of the idea 】

1. Second kill business features ： Instantaneous flow , Repeated requests , Purchase quantity limit

2. Secsha is deployed as a separate micro service

3. front end    Static state , Current limiting

4. Back end    line up , cache , Fuse , Current limiting

【 Storage performance estimation 】

【 register 】

   Less than... New users are registered every day  1  ten thousand , You can ignore

【 Sign in 】 

 

Million user login information

【 goods 】 

 

at present

 

10  Categories  , Each category  20  A commodity , goods   Number  200

【 Order 】  

Load balancing of computing architecture

The number of second kill goods is limited , Order writing quantity , View quantity   negligible

【 Storage architecture 】

【 Computational performance prediction 】

【 register 】

   Less than... New users are registered every day  1  ten thousand , You can ignore

【 Sign in 】  

  Million user login information

【 Browse products 】  

 

The exposure rate of seckill products is high , Suppose every user browses  20  Time , Browse   Time focused on   The second kill started

   front  10 Minutes and after 10 minute ,QPS mean value ：100 ten thousand *20/20*60 ≈ 2 ten thousand /s

【 Order in seconds 】

  

The number of second kill goods is limited , hypothesis   Yes  30% The customer participates in the second kill , After the second kill  30  Seconds   Purchase completed .

  TPS  mean value ：100 ten thousand *0.3/30 ≈ 1 ten thousand /s

【 Load balancing of computing architecture 】

【 Cache architecture of computing architecture 】

【 Scalable architecture 】

【 High availability Architecture 】