Perceiver attention

Pinned implementation and paper LDLM @ e18c42a, not yet public · arXiv:2605.07933v1 · OpenWebText · 1024 · checkpoint, tokenizer and saved statistics not verified · How to read

Latent encoder › 6 encoder blocks › Perceiver attention

Merge heads

×

no parameters

Concatenate the 12 heads into 768 features.

[B, 12, T, 64][B,\,12,\,T,\,64]
→  [B, T, 12, 64]\to\;[B,\,T,\,12,\,64]
→  [B, T, 768]\to\;[B,\,T,\,768]
in
OO [B batch, 12 heads, T positions, 64 head features]
out
oo [B batch, T positions, 768 d]
Explanation

Heads are concatenated in order: head ii fills features 64i,…,64i+63{64i},\dots,{64i+63}.

Sources1

Direct evidence

Both streams are normalized; queries come from one stream, keys and values from both, concatenated along positions; queries and keys are normalized per head; attention runs over all positions with softcap; the heads are merged and projected.

The implementation, pinned at revision e18c42acdfb7, not yet public