Tesla backend interview (part)

HR informs that if the interview is passed, it will be transferred to .net-_-

round1

• Have you ever used the new version of Java, do you know what features it has? A: No. Q: We are basically using JDK11, and some new projects use JDK17. Refer to answer ¹ :

• • ZGC: A Scalable Low-Latency Garbage Collector
• • Epsilon: A No-Op Garbage Collector. Several usage scenarios of no-op GC: performance testing, extremely short job tasks, etc.
• • New methods such as isBlank in the String class
• • Running Java File with single command：You don’t need to compile the java source file with javac tool first. You can directly run the file with java command and it implicitly compiles.
• • Local variables can be declared using the keyword var

• Lucene data structure

• Do you understand graphQL? Reference: GraphQL and REST

• What is the basis for setting the number of Kafka partitions when creating a topic? Reference ² : Assuming that for a single partition, the achievable throughput of the producer end is p, the achievable throughput of the consumer end is c, and the expected target throughput is t, then the number of partitions required by the cluster is at least max(t/p, t/c). On the producer side, the throughput of a single partition will receive the confirmation type (synchronous and asynchronous) (note: synchronous means that the msg is copied to all replicas before sending an ack to the producer, and asynchronous means that the msg is written to the leader successfully and the producer is sent back to the ack), The effect of configuration parameters such as replication factor.

• Have you ever used kafka connectors? Does CDC know? References ³ , ⁴

• How do you know if a service is healthy? Related information: health check, registration center, etc. ⁵

• The compatibility issue of Protobuf of grpc. Is it allowed to change the field type?

round2

• How do you do the authentication and authentication of your system
• How do you do distributed transactions across services
• What branches do you have for Git. How does CICD work

In the end, HR told me that the others were not bad, but I was stuck in English, not fluent enough -_-

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1. Overview of new features in Java 11 ,
   Java 11 Features ↩︎

2. How to choose the appropriate number of Topics/Partitions for the Kafka cluster ,
   how to determine the appropriate number of topics/partitions for the Kafka cluster (translation) ↩︎

3. The application of kafka-connect real-time stream mentioned its simple comparison with Canal↩︎

4. https://docs.confluent.io/kafka-connectors/self-managed/kafka_connectors.html#kafka-connectors ↩︎

5. System high availability health checks and health metrics↩︎