8-year test summary, performance test-full link stress test core link detailed explanation, a little bit transparent...

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foreword

Throws a question: what is the core link?

Many companies have their own core business scope, and these core businesses are often the main source of corporate profits.

Taking e-commerce companies as an example, they provide users with product purchase services, and merchants with product management, listing and pricing display. Most of the profits are service fees and advertising related expenses brought about by matching users and merchants.

The so-called core link can be understood from a technical point of view:
in the core application corresponding to the core business, the path through which the most important request traffic to ensure the realization of corporate profits is the core link.

It’s a bit of a mouthful to say this, but to be more straightforward: which interfaces will affect users’ order and payment, and which are the core links.

Attached below is a common flow chart of the core link of an e-commerce enterprise:

Why determine the core link?

Students who do testing are very familiar with this point. Whether it is the priority of requirements review, or the smoke case provided for development when writing test cases, or even prioritizing bugs when submitting bugs, they will be prioritized. What is the reason? Woolen cloth?

Because the situation we face most of the time is to ensure the quality of delivery within the limited time and human resources, but also to complete as many tasks and needs as possible.

Especially for complex projects like the e-commerce Double 11 promotion, there are too many things to do, time and human resources are limited, and there are many business scopes and applications involved. At this time, a trade-off needs to be made.

Some businesses and applications that are not covered may have some problems, but if the stability of the core business and applications can be guaranteed to better achieve the business goals of the enterprise, then these losses are still acceptable.

And it's not that we don't pay attention to non-core business and application stability, but solve this problem through other technical means such as current limiting, downgrading, circuit breaker or business entrance closure.

How to sort out the core links?

The above figure is an example of an e-commerce enterprise order application, and a simple business call link is sorted out. Here is a dismantling explanation.

Determine the core business scope as trading business;
determine that the core application includes order applications;
the interfaces with the highest proportion of traffic requests in the order service are order confirmation, order creation, order list and order details;
determine these four interfaces by means of link tracking Which services and interfaces or middleware are the downstream dependencies calling;
determine whether the relationship of these downstream dependencies is strong or weak, and whether there is a calling relationship of external three-party services;
strong dependencies are broken, weak dependencies are downgraded, and the interface itself of the order service For current limiting, external third-party services rely on mocking;

What is the purpose of sorting out the core links?

The schematic diagram is as follows:

The main purpose of sorting out the core links is to obtain the traffic model, know the strong and weak dependencies, and formulate a stability plan.

traffic model

A case, review here again:

The unit price per customer is 500, and the GMV per day is 1 billion, so the payment order volume is 1 billion/500=200W;

Assume that the daily payment order volume is 50W, the payment conversion rate is 40%, and the order payment QPS peak value is 200. It is estimated that the payment conversion rate during the big promotion is 60%, then it can be obtained: the peak order payment QPS of the big promotion is (200/40%) 60% (200W/50W) = 1200QPS. This 1200QPS is a guaranteed value. Generally, in order to leave a certain amount of redundant space, it will be increased by 30%, that is, the QPS for order payment is estimated to be 1500;

E-commerce shopping guide browsing order payment conversion link is generally: home page → product details → create order → order payment → payment success, this process is a conversion logic similar to a funnel.

Assuming that the conversion rate of home page → product details is 40%, product details → create order conversion rate is 40%, create order → order payment conversion rate is 40%, then it can be obtained: create order QPS is 1500/40%=3750, product details QPS is 3750/40%=9375, home page QPS is 9375/40%=23437;

After determining the expected traffic index of the core link, the evaluation range can be continuously expanded through the dependencies between links until a traffic model is formed.

The traffic model is a funnel-like conversion process, and there are different conversion rates from the traffic entrance to the bottom DB. The further down the link, the lower the QPS.

Evaluate expected traffic through conversion rate and sort out link dependencies to form a traffic model.

What needs to be noted here is that the user’s daily traffic model is different from that during the big promotion, because the user’s goal is clearer during the big promotion, so the conversion rate is higher. To convert from business indicators to technical indicators, you need to be familiar with the business, not just focus on technology.

Strong and weak dependence

After obtaining the strong and weak dependencies through the traffic model and combing, the next step is to set various stability plans according to the dependencies.

One thing to note here is that many plans need to communicate with the business or product in advance, such as active downgrade or closing of the business entrance, because these downgrade actions need to be known and cooperated by the business side, not just a technical one. action.

Stability plan

The main purpose of the stability plan is to ensure the stability of online applications under the impact of traffic peaks during the e-commerce double 11 period, and provide a good guarantee for the achievement of business goals.

There are also different types of stability plans. In other words, different plans should be set in different situations, rather than a general thing. It needs to be evaluated according to the technical facilities of the enterprise and the specific conditions of the technical team.

The most common stability plan is the current-limiting fuse downgrade we mentioned above, and the more advanced ones are disaster recovery, master-standby switchover, business entrance closure, and even power-off protection.

The following is the most complete software test engineer learning knowledge architecture system diagram in 2023 that I compiled

1. From entry to mastery of Python programming

2. Interface automation project actual combat

3. Actual Combat of Web Automation Project

4. Actual Combat of App Automation Project

5. Resume of first-tier manufacturers

6. Test and develop DevOps system

7. Commonly used automated testing tools

Eight, JMeter performance test

9. Summary (little surprise at the end)

Success comes from your own hard work and dedication, not relying on others or random luck. As long as you have faith and enthusiasm, persevere in your efforts, move forward courageously, and believe in yourself, you will be able to achieve greater achievements in the future.

One hard work and one harvest, hard work will definitely pay off. Setbacks and failures are only temporary, don't give up on your dreams. Only with a firm belief and continuous pursuit of excellence can we achieve a beautiful life.

Everyone has their own dreams and goals, but only those who are not afraid of failure and continue to struggle can finally achieve them. Persistence and courage, success is not far away!