Latest revision as of 15:51, 6 August 2020

Lake Crest is a neural processor microarchitecture designed by Nervana.

Process Technology[edit]

Lake Crest is fabricated on TSMC's 28 nm process.

Architecture[edit]

Lake Crest was designed from the ground up for deep learning. The architecture itself is a tensor-based architecture, meaning it's optimized for blocks of compute instead of operating on scalars (as would a traditional Intel CPU would).

• Tensor-based architecture
  • Nervana Engine
• Flexpoint number format
• No caches
  • Software explicitly manages all on-chip memory
• HBM2 memory
  • 32 GiB of in-package memory
  • 8 Tbit/s bandwidth
• 12 x Inter-Chip Links (ICL)
  • bi-directional high-bandwidth direct chip-to-chip interconnect
  • 100 GB/s (1,200 GB/s aggregate)

This list is incomplete; you can help by expanding it.

Block Diagram[edit]

Chip[edit]

Processing Cluster[edit]

This section is empty; you can help add the missing info by editing this page.

Memory Hierarchy[edit]

• 32 GiB on-package HBM2
  • 1 TiB/s

Die[edit]

Nervana stated that Lake Crest is "near-reticle size" implying the die size is likely around the 650-750 mm².

• TSMC 28 nm process
• 650-750 mm² die size

Additional Shots[edit]

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  Lake Crest Accelerator PCIe card (internal view)

Bibliography[edit]

• Rao, N. (2016, November). Pathfinding and Hardware Deep Dive. 2016 AI Day, San Francisco.
• Rao, N. (2018, May). Keynote presentation. 2018 AI DevCon, San Francisco.