Distributed Database Engineering Intern · Qingyun Program
Tencent · Distributed Database R&D Center
Contributed to a production analytical database, with work spanning distributed SQL execution, observability, and compute-node reliability.
About Me
I am a direct-track doctoral student in Computational Mathematics at Zhejiang University. My work spans production database systems and high-order numerical computing. During a one-year Qingyun internship at Tencent, I worked on distributed SQL execution, performance profiling, and compute-node reliability.
My doctoral research focuses on fourth-order finite-volume and multigrid methods for elliptic and incompressible-flow problems on complex geometries. I am interested in AI infrastructure, high-performance C++ systems, and quantitative infrastructure.
Experience
DetailsFull-Stack Strategy Engineer
Hangzhou Higgs Investment Management Co., Ltd.
Developed market-data infrastructure and internal analysis tools for quantitative research and live-trading operations.
Selected Projects
DetailsDatabase Systems
Distributed Query Profiling
Produced query/operator/node/thread diagnostics and used them to identify lock contention introduced by high-frequency instrumentation.
Numerical Computing
Fourth-Order Cut-Cell Multigrid Solver
Achieved approximately fourth-order convergence and near-optimal refinement complexity; a sparse bottom solve reduced one benchmark from 118.770 s to 4.441 s (26.7×).
Computational Fluid Dynamics
Density-Stratified Flow Solver
Verified fourth-order accuracy in manufactured-solution studies and obtained results consistent with reference experiments.
Publication
Jiyu Liu, Zhixuan Li, Jiatu Yan, Zhiqi Li, and Qinghai Zhang (2026).
A Fourth-Order Cut-cell Multigrid Method for Solving Elliptic Equations on Arbitrary Domains
arXiv:2601.02975 (v3) · Preprint; journal submission has not yet been made.