Interview with Zhang Jinjun on JD.com’s CallGraph Platform and Microservice Governance

Zhang Jinjun, head of the Service Governance team in JD.com’s Infrastructure Department and a lecturer at the JD Technology 11.11 Infrastructure Summit, has sixteen years of front‑line R&D experience, including storage technology and middleware development such as the JSF remote‑call framework.

He introduced the CallGraph platform, which was created to address the growing dependency and troubleshooting problems caused by the rapid expansion of microservices at JD.com. The platform provides a topological view of service dependencies, heat‑maps of call frequency, and resource‑usage assessments, enabling quick identification of problematic services and their downstream impacts.

When asked why CallGraph is emphasized, Zhang explained that microservice adoption leads to a proliferation of services, creating complex dependency chains that are hard to trace. Without a visual dependency map, pinpointing the source of an issue across long, cross‑departmental call chains becomes extremely difficult.

He described how CallGraph solves these issues by automatically attaching a trace ID to business logs, presenting tree‑structured dependency graphs, and showing relationship diagrams that indicate the degree of coupling between services.

Looking ahead, JD.com plans to expand CallGraph into a global call‑graph map that visualizes all application interactions across the company, similar to a geographic map, and to integrate with the JDOS platform for resource‑usage analysis, helping business units and senior management make informed decisions.

Zhang believes that CallGraph will become as essential to distributed tracing as RPC frameworks and message queues, especially as more companies adopt microservices. Future developments may include multi‑dimensional monitoring tools and machine‑learning‑driven automated problem‑resolution suggestions.

All PPTs, texts, and videos from the JD Technology Infrastructure Summit will be released via the “JD Technology” WeChat public account.