by Xiaokang Zhang | Sep 29, 2021 | Sociology
中国今天的经济成就主要归功于改革开放，但我们对改革开放的印象常常停留在宏达的政治叙事上：小岗村的联产承包、邓小平南巡讲话、设立经济特区、加入WTO等。对于中国从计划经济变成市场经济的具体过程，我们却缺少细节。其实除了这些重大历史事件，国企破产和现代化改革、设立股票交易所、建立现代金融体系等改革，都对中国当代的经济面貌影响重大。这其中，1994年的分税制改革又尤为重要。...
by Xiaokang Zhang | Sep 18, 2021 | Software Architecture
Cache can help reduce the load to the database and improve the service performance, however, designing and using the cache in the optimal way is one of the most tricky problems. In Doordash’s monolithic world, there were many anti-patterns cache usage, which makes...
by Xiaokang Zhang | Sep 18, 2021 | Software Architecture
Database is oftentimes the bottleneck of service scalability and reliability. Between 2018 and 2020, Doordash experienced multiple site wide outages during our traffic peak hours due to database issues. Before we are able to break down the monolithic service, we need...
by Xiaokang Zhang | Sep 16, 2021 | Software Architecture
ORM is widely used in Doordash’s Django monolithic service. Like many other technologies, it enabled the developer to focus on the business logic. However, it became a major scalability bottleneck as the service grew. In this chapter, I am going to talk about the bad...
by Xiaokang Zhang | Sep 16, 2021 | Software Architecture
In the monolithic world, doordash service only has two layers: a python Django monolithic service as the backend, and the client layer, including the web and mobile clients. The simple architecture worked well when the business and the team were small, as it enabled...