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 decoder › 6 decoder blocks › Perceiver attention

Query, key and value projection

×

learned

One matrix maps the normalized decoder state to queries, keys and values, 768 features each.

pa=[ q  ka  va ]=rˉn WQKV{\htmlData{light=self-parts self-projection}{p^{a}}}=[\,{\htmlClass{vl-stream-q}{q}}\;{\htmlClass{vl-stream-k}{k^{a}}}\;{\htmlClass{vl-stream-v}{v^{a}}}\,]={\htmlData{light=query-norm}{\bar r_n}}\,W_{QKV}
in
rˉn\bar r_n [B batch, T positions, 768 d]
out
pap^{a} [B batch, T positions, 2304 q, k, v]
parameters
1,769,472 · × 6 blocks = 10,616,832
Parameters

1,769,472 parameters per instance.

Exact per-instance accounting
ComponentCalculationParameters
Weight matrix768×2,304768 \times 2{,}3041,769,472
Per-instance total1,769,472

This projection has no bias parameter.

The reference module holds the weight output by input, [out, in].

Across 6 independent blocks: 1,769,472×6=10,616,8321{,}769{,}472 \times 6 = 10{,}616{,}832 parameters.

Derived from the configured matrix dimensions; checkpoint tensors have not been independently counted.

Sources2

Direct evidence

Perceiver attention owns an RMSNorm for each of its two streams, a fused query–key–value projection of the query stream, a fused key–value projection of the other stream, RMSNorms for each head’s queries and keys, and an output projection; no bias.

The implementation, pinned at revision e18c42acdfb7, not yet public

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