
Jerry Peng contributed to the apache/spark repository by building and enhancing real-time data processing capabilities, focusing on Spark Structured Streaming and Kafka integration. He implemented Real-Time Mode (RTM) triggers and interfaces, enabling low-latency analytics and robust end-to-end testing for both Scala and Python (PySpark) clients. His work included optimizing deserialization in Spark’s streaming path, improving throughput and reducing CPU usage, and strengthening error handling in Avro schema parsing. Jerry also addressed reliability through expanded test coverage and metric reporting fixes, demonstrating depth in backend development, stream processing, and data engineering using Scala, Java, and Python across complex distributed systems.
March 2026 monthly summary for apache/spark: Delivered two reliability-focused enhancements that improve observability and error handling. Implemented a RocksDBStateStoreProvider metric reporting fix with regression tests, and introduced AvroUtils.parseAvroSchema to robustly handle Avro parsing errors by wrapping NPEs in SchemaParseException. Updated all impacted components to use the new parser, ensuring consistent error reporting across modes. Result: more accurate metrics, stable schema validation post-Avro upgrade, and reduced troubleshooting effort. Demonstrates proficiency in Spark SQL, RocksDB integration, Avro parsing, and comprehensive test coverage.
March 2026 monthly summary for apache/spark: Delivered two reliability-focused enhancements that improve observability and error handling. Implemented a RocksDBStateStoreProvider metric reporting fix with regression tests, and introduced AvroUtils.parseAvroSchema to robustly handle Avro parsing errors by wrapping NPEs in SchemaParseException. Updated all impacted components to use the new parser, ensuring consistent error reporting across modes. Result: more accurate metrics, stable schema validation post-Avro upgrade, and reduced troubleshooting effort. Demonstrates proficiency in Spark SQL, RocksDB integration, Avro parsing, and comprehensive test coverage.
January 2026: Delivered Real-Time Mode (RTM) trigger for PySpark, enabling real-time execution of stateless queries without UDFs by updating DataStreamWriter and related protobuf definitions. Also added Spark Connect compatibility and an initial test. Addressed test failures by aligning RTM trigger method signatures for Spark Connect. This work reduces latency in real-time analytics, broadens client support, and lays a solid foundation for future RTM enhancements.
January 2026: Delivered Real-Time Mode (RTM) trigger for PySpark, enabling real-time execution of stateless queries without UDFs by updating DataStreamWriter and related protobuf definitions. Also added Spark Connect compatibility and an initial test. Addressed test failures by aligning RTM trigger method signatures for Spark Connect. This work reduces latency in real-time analytics, broadens client support, and lays a solid foundation for future RTM enhancements.
December 2025 — Focused on strengthening Real-Time Mode (RTM) reliability via end-to-end testing in Apache Spark. Delivered RTM end-to-end tests to improve coverage for critical real-time workflows, enabling earlier regression detection and safer production deployments. No user-facing changes introduced by this work; tests are additive and non-invasive. This effort reduces production risk and provides a solid foundation for future RTM improvements.
December 2025 — Focused on strengthening Real-Time Mode (RTM) reliability via end-to-end testing in Apache Spark. Delivered RTM end-to-end tests to improve coverage for critical real-time workflows, enabling earlier regression detection and safer production deployments. No user-facing changes introduced by this work; tests are additive and non-invasive. This effort reduces production risk and provides a solid foundation for future RTM improvements.
November 2025 (2025-11) monthly summary for the Spark Apache project focused on Real-time Mode (RTM) enhancements for Kafka integration. Delivered RTM support for Kafka Source and Sink, enabling real-time queries and a guided allowlist to clarify supported features and prevent unexpected results. Implemented core RTM interfaces (KafkaMicroBatchStream SupportsRealTimeMode and KafkaPartitionBatchReader Extend SupportRealTimeRead) to align with RTM architecture. Introduced guardrails to fail fast on unsupported features in RTM, improving user guidance and reducing misconfigurations. Expanded test coverage across RTM paths to validate behavior and ensure reliability. Strengthened the platform’s capability for real-time analytics on Kafka streams, enabling customers to derive timely insights with Spark streaming.
November 2025 (2025-11) monthly summary for the Spark Apache project focused on Real-time Mode (RTM) enhancements for Kafka integration. Delivered RTM support for Kafka Source and Sink, enabling real-time queries and a guided allowlist to clarify supported features and prevent unexpected results. Implemented core RTM interfaces (KafkaMicroBatchStream SupportsRealTimeMode and KafkaPartitionBatchReader Extend SupportRealTimeRead) to align with RTM architecture. Introduced guardrails to fail fast on unsupported features in RTM, improving user guidance and reducing misconfigurations. Expanded test coverage across RTM paths to validate behavior and ensure reliability. Strengthened the platform’s capability for real-time analytics on Kafka streams, enabling customers to derive timely insights with Spark streaming.
October 2025: Focused on enabling real-time analytics in Spark Structured Streaming by delivering the foundational Real-time Mode (RTM) capability in a staged approach. Completed trigger introduction, API scaffolding for RTM sources, and end-to-end RTM testing infrastructure with memory sources/sinks and offset management. These changes lay the groundwork for low-latency, time-based streaming and improve reliability for live data processing; business value comes from reduced latency, earlier insight, and better testing coverage for RTM workloads.
October 2025: Focused on enabling real-time analytics in Spark Structured Streaming by delivering the foundational Real-time Mode (RTM) capability in a staged approach. Completed trigger introduction, API scaffolding for RTM sources, and end-to-end RTM testing infrastructure with memory sources/sinks and offset management. These changes lay the groundwork for low-latency, time-based streaming and improve reliability for live data processing; business value comes from reduced latency, earlier insight, and better testing coverage for RTM workloads.
November 2024: Implemented a focused performance optimization in Spark's streaming path by deserialization initialization. Per-partition initialization of key/value deserializers in TransformWithStateExec reduces overhead, improving throughput and lowering CPU usage in batch processing. Associated with SPARK-50437.
November 2024: Implemented a focused performance optimization in Spark's streaming path by deserialization initialization. Per-partition initialization of key/value deserializers in TransformWithStateExec reduces overhead, improving throughput and lowering CPU usage in batch processing. Associated with SPARK-50437.

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