01 About
Charles Benello
I'm a software engineer and systems researcher at the University of Chicago. I'm currently at Amazon Web Services in Palo Alto as a Software Development Engineer Intern on the Redshift query optimizer team, working on the data-sharing query path, having wrapped an internship at Alter Domus building AI systems for financial asset management earlier this year. My background spans database internals, high-performance computing, and full-stack development.
I design and implement large-scale systems - from parallel sorting algorithms in Rust to GPU-accelerated query processing in CUDA to production AI pipelines in Python. I've published in VLDB and CIDR, working with Professor Aaron Elmore at UChicago's ChiData Lab and Professor Anastasia Ailamaki at EPFL's DIAS Lab.
Education
University of Chicago
Master's degree / Financial Mathematics
Jun 2025 - Mar 2027
University of Chicago
BS / Mathematics and Computer Science (Systems specialization); Minor in Korean
Sep 2021 - Jun 2025
Dean's List
St Paul's School
2015 - 2021
Mathematics: A*; Further Mathematics: A*; Computer Science: D1
Current Work
- SDE intern at AWS Redshift (Palo Alto): re-architecting metadata loading on the data-sharing query path
- Research: adaptive sort configuration across disaggregated and cloud-native hardware
- Research: GPU-accelerated compression for analytical databases
- Evaluating policy compliance gaps in Rust LLM code generation benchmarks
- CovTSP: near-optimal transit coverage solver using real GTFS network data
Experience

Software Development Engineer Intern
AWS Redshift·Aug 2026 - Nov 2026
On the Redshift query optimizer team in Palo Alto, working on the data-sharing query path - the route a query takes when it reads another warehouse's data.
- Cut end-to-end latency ~15% and p99 tail latency ~30% in benchmarks on contended data-sharing workloads by re-architecting the query path to fetch remote storage metadata just-in-time, after workload-management admission rather than before it
- Eliminated ~10% of remote metadata downloads in benchmark workloads by proving the deferral safe - tracing planner dependencies across path generation, cardinality estimation, and result caching, then re-sourcing per-slice table statistics from lightweight catalog metadata
Skills
Research + Publications
Research Focus
- Large-scale data processing
- Database internals
- High-performance systems
- GPU-accelerated compression
Research Highlights
- Predictive modelling for CrocSort configuration on disaggregated and cloud-native hardware - finding diminishing returns in thread counts and near-optimal config selection without brute-force sweeps
- Resource-adaptive query execution with paged memory management
- GPU-accelerated compression: decompression strategies, workload modelling, and cost-based trade-offs
- Policy gap in Rust code generation benchmarks: showing that code passing SWE-bench tests can still violate project-defined safety and style policies
- Exploring external sort on GPUs, disaggregated hardware, and cloud-native environments - understanding how storage/compute separation and elastic resources reshape sorting performance
Advisors + Labs
- Professor Aaron Elmore (ChiData Lab, University of Chicago)
- Professor Anastasia Ailamaki (DIAS Lab, EPFL)
Publications
CrocSort: Resource-Efficient, Skew-Resilient Parallel External Merge Sort
Riki Otaki*, Charles Benello*, Fuheng Zhao, Aaron J. Elmore, Goetz Graefe
VLDB 2026
* Equal contribution
Getting the Most Out of External Sorting in Cloud and Disaggregated Environments
Charles Benello, Riki Otaki, Fuheng Zhao, Aaron J. Elmore, Goetz Graefe
Under review
Resource-Adaptive Query Execution with Paged Memory Management
Riki Otaki, Jun Hyuk Chang, Charles Benello, Aaron J. Elmore, Goetz Graefe
CIDR 2025
Benchmarks Pass, Policies Fail: A Policy Gap in Rust Code Generation Evaluation
Matt Gaughan, Charles Benello, Keixin Pei
In preparation
WIP
Projects




CovTSP
Covering TSP solver for transit coverage optimization. Formalizes the London Tube Challenge into a provably near-optimal solver for any GTFS city.