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Thea Lauren
Thea Lauren

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Beyond the VM: Why vLLM and FlashAttention need Bare Metal GPUs 🚀

Hello, builders! 👋 If you're working on LLM inference using frameworks like vLLM, TGI, or Triton, you already know that inference is memory-bandwidth bound, not compute bound.

We just published a massive technical breakdown on the Leo Servers blog detailing why standard cloud VMs actively sabotage transformer attention mechanisms.

Technical highlights from the post:

Continuous Batching Jitter: How cloud hypervisor memory ballooning directly interferes with PagedAttention, causing catastrophic OOM errors or throughput degradation.

Kernel-Level Bottlenecks: FlashAttention minimizes HBM reads/writes by tiling compute within SRAM. Virtualized GPU environments introduce driver-level overhead that negates these gains. Bare metal preserves it.

NVLink vs. PCIe: Why tensor parallelism for 70B+ models absolutely requires the 900 GB/s bidirectional bandwidth of NVLink 4.0, and why cloud network abstraction slows down all-reduce operations.

If you're deploying in production, you need exclusive hardware access. We break down the exact VRAM floors for models (7B to 400B+) and how to choose the right cluster.

For more details, read more and visit the blog link: [https://www.leoservers.com/blogs/category/why/llms-require-bare-metal-gpus/]

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