Izzet Yildirim

Izzet Yildirim

PhD candidate in computer science, Illinois Tech, Chicago

I spend my time on the moments when AI is waiting: a training job blocked on its next batch, an agent stuck while its tools read data off storage. I trace where that time goes, down to the file system, and build systems that hide it.

Before my PhD I spent more than ten years in industry, the last eight at VeriPark, leading a 20+ engineer division by the end. From 2022 to 2026 I worked with Lawrence Livermore National Laboratory, and I interned at Argonne National Laboratory in 2024.

I finish in May 2027 and I’m looking for AI-infrastructure and research-scientist roles starting that summer. Get in touch.

Try
Each project covers part of one loop:observe→analyze→diagnose→optimize

LLM agents

Agents read data in ways no earlier workload did.

AgentStage1.74× fastereScience ’26
optimize· first author

Uses an agent’s thinking time to stage data from cold storage into a tiered node-local cache (memory, then NVMe) before the agent asks for it.

1.74× faster sessions on average (up to 2.34×) at under 1% overhead.
Correct Is Not I/O EfficientGCASR ’26 poster
observe· first author

Characterizes the I/O behavior of LLM agents working on scientific data: an agent can reach a correct answer while doing far more I/O than the task needs.

StageOnceSC ’26 poster
optimize· first author

Speculative cross-job data staging for fleets of LLM agents.

Abstract only until it is presented at SC ’26.

ToolFuseSC ’26 poster
optimize· first author

Provenance-aware, in-flight coalescing of redundant agent tool calls.

Abstract only until it is presented at SC ’26.

The first I/O benchmark for scientific LLM agentsdetails after publication

Deep learning training

Keeping GPUs fed during distributed training.

GDSightPDSW ’26
observe+analyze· first author

Per-operation, cross-layer attribution for GPUDirect Storage: where a single GPU read spends its time, from the application down to the device.

DFAnalyzersoftware · LLNL
analyze· first author

Layer-by-layer analysis of DFTracer traces, from application events down to POSIX calls. I built it at LLNL.

DFTracerSC ’24
observe· co-author

An analysis-friendly data-flow tracer for AI-driven workflows, developed at LLNL.

DL I/O at Argonneinternship ’24
analyze· first author

Profiled Transformer and DLRM data loading on the A100-based Polaris supercomputer with DLIO, finding access phases that guide Lustre striping and transfer sizes.

Online tuning of data movement for distributed trainingdetails after publication
Diagnosing and fixing deep learning I/O bottlenecksdetails after publication

HPC workflows

Finding I/O bottlenecks in scientific workflows.

WisIO144× more foundICS ’25
analyze+diagnose· first author

Automated I/O bottleneck detection for HPC workflows, using correlated views of the same trace from several perspectives.

Finds 144× more I/O bottlenecks than existing tools, 11× faster.
IOMaxPDSW ’23
analyze· first author

Makes out-of-core analysis of very large I/O traces fast on HPC systems.

ORION6.8–36× less dataProTools ’26
observe· co-author

An observability framework for hybrid, workflow-centric I/O monitoring on HPC systems. I co-authored it.

Cuts trace volume 6.8–36× while keeping 100% of the top-k bottlenecks.
Recorderpreprint · under review
observe· co-author

Comprehensive parallel I/O tracing and analysis across HPC I/O libraries.

Rabbit I/OREX-IO ’25
optimize· co-author

I/O optimization for an exascale implicit kinetic plasma simulation on LLNL’s Rabbit near-node NVMe storage.

Multiple I/O MetricsSC ’23 poster
diagnose· first author

Shows that I/O time, bandwidth, and IOPS each expose different bottlenecks in HACC, Montage, and CM1.

DigIOSC ’22 poster
diagnose· first author

DigIO, a tool that finds I/O bottlenecks automatically from a multifaceted view of a workload’s traces; the precursor to WisIO.

Containerized OrangeFSSC ’21 poster
analyze· first author

Compares five container runtimes hosting the OrangeFS parallel file system; Singularity came closest to bare metal.

first authorco-authorunder review
Nov 2025Nov 2026