Profile cover
E

AI GPU Memory Defragmentation Engineer

Evan Ferrari

Full-time · Job · Los_Angeles

About the role

GPU memory fragmentation is the silent killer of training throughput. A cluster that should deliver 94% MFU sits at 71% because memory allocations from terminated jobs leave unusable gaps, forcing new jobs to spin up on fresh nodes rather than reusing partially available ones. At the scale we operate — 18,000 A100s across five data centers — every percentage point of MFU translates to millions of dollars per year. We need a staff engineer who understands GPU memory management at the allocator level: how PyTorch's caching allocator fragments across training runs, how CUDA driver memory interacts with framework-level allocation, and what defragmentation strategies work in practice without introducing latency spikes that hurt running jobs. This is a combination of systems programming, performance engineering, and distributed infrastructure. You'll own the memory management layer of our ML infrastructure: designing defragmentation policies, building monitoring that surfaces fragmentation before it impacts jobs, and implementing the scheduling changes that let us pack jobs more efficiently. The platform team is 12 engineers; this is a staff-level IC role with no management scope.

Responsibilities

  • Design GPU memory defragmentation policies for multi-tenant training clusters
  • Build fragmentation monitoring and alerting integrated with cluster scheduler
  • Implement memory-aware job scheduling to maximize cluster MFU
  • Analyze memory allocation patterns across PyTorch, JAX, and TF workloads
  • Profile and eliminate allocation hot spots in high-throughput training pipelines
  • Benchmark defragmentation impact on training throughput and job startup latency

Requirements

  • 7+ years in ML infrastructure or systems programming
  • Deep expertise in GPU memory management: CUDA allocators, driver memory, framework caches
  • Experience with cluster schedulers (SLURM, Kubernetes, or custom) at GPU scale
  • Strong C++/Python skills with performance profiling experience
  • Track record improving cluster efficiency by 10%+ through infrastructure changes

Benefits

  • Fully remote with complete schedule autonomy
  • Top-of-market total compensation
  • Significant equity package
  • Comprehensive health benefits
  • Annual $8,000 equipment and learning budget

Keep exploring related roles

Use these topic pages to discover more roles in the same hiring cluster.

Job Type

Full-time

Level

Senior

Language

English

Salary Range

$200k+ / year

AI Expertise

MLOps & AI Infrastructure

Skills

python kubernetes docker aws pytorch fastapi

Ready to apply for this role?

Create a free talent account in under 2 minutes.

  • Apply to verified AI companies
  • Get AI-matched job recommendations
  • Message hiring managers directly
  • Build your public AI talent profile

Interested in this role? Create your free profile to apply.

Apply — create free profile