Zhijia Li

About Zhijia Li

SDE at AWS Lambda

Experience

1. Software Development Engineer

   Amazon Web Services (AWS)

   Aug 2022 — Present · Seattle, WA, US

   Contributed to AWS Lambda’s SnapStart, a feature to reduce cold invoke time for serverless invokes- Implemented and maintained a Rust-based linux userspace file system for AWS Lambda and AWS Kepler- Optimized an Rust-based asynchronous cache putting API and integrated this API with Linux Kernel-based Virtual Machine (KVM) by Golang gRPC to cache user data, improved Lambda P99 cold invoke latency by 40%- Collaborated with others on a project utilizing an open-source multithread downloading API, enabling direct transfer of kernel memory data from AWS S3 to KVM kernel, resulting in a significant cost saving of cache usage by 200 million per year- For the project mentioned above, integrated the multithread downloading API, implemented data decryption and networking namespace setting, led load tests, and ensured seamless final code integration- Optimized this project by adding an extra thread to on-demand download data triggered by kernel fault signals, improving availability by 5% for enhanced performance.Identified and addressed team-level unit test flaky issues by upgrading compiler and introducing a test execution model, isolating tests into different processes to ensure reliability and stability- Designed and implemented a performance analysis method that calculates precision and recall metrics about data retrieved from a collection, significantly improving performance visibility.Consistently demonstrated a proactive approach to issue mitigation during on-call rotations, effectively reducing the overall number of incidents and ensuring optimal service reliability.