Llama 3 is a dense decoder-only transformer: GQA with 8 KV heads, RoPE at base 500,000, SwiGLU, a 128K-token vocabulary built from tiktoken plus 28K added tokens, and staged continued pretraining from 8K to 128K context. The report leads with data scale (15.6T tokens, ~50/25/17/8 knowledge/reasoning/code/multilingual mix) and a six-round post-training pipeline of SFT, rejection sampling, and DPO with formatting-token masking. The 405B flagship is the largest dense model in the atlas and the reference variant; the 8B/70B siblings share the block with shallower, narrower stacks. Architecturally it is the same family as the existing meta-llama-3.1 record — the report's results in fact describe the Llama 3.1 models — so this record's value is as the base-herd source: the pretraining recipe, staged context extension, and the explicit release of all three sizes under the Llama 3 Community License.
What the report claims is novel
A herd of three models (8B/70B/405B) released under the Llama 3 Community License [Abstract / §1]
Data quality and quantity scaling: 15.6T tokens with a ~50/25/17/8 mix [§1 / §3.1]
Staged continued pretraining from 8K to 128K context [§3.4.2]
Atlas assessment: Structurally refines the Llama 3.1 record's architecture (same family, this record covers the base April-2024 releases; the report's results refer to the 3.1 models). GQA + RoPE-500K + 128K context were already in the atlas via Llama 3.1; nothing structurally novel within atlas scope, but this is the canonical source for the base herd.
Relation to the atlas
Lineage in
dense decoder-only Transformer (self-attention + FFN blocks) from Transformer (Vaswani et al. 2017)
RoPE with base 500,000 from RoFormer / Llama line (per report §3.2 context)
Vocabulary combines 100K tokens from the tiktoken tokenizer with 28K additional tokens for non-English support; improved compression vs Llama 2 tokenizer (§3.2)[11]