Query heads

61 transformer blocks › 58 MoE blocks › Sparse latent attention › Query heads

Unrotated query part

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tensorq_pe · 563

Each head’s 64 rotary features before rotation.

shape
QpeQ^{\mathrm{pe}} [B batch, 128 heads, 1 position, 64 rotary]
Sources

Contextual evidence from Split rotary heads

Queries are produced through a low-rank latent, split into a non-rotated and a rotated part, and rotated.

mla-queries · deepseek-ai/DeepSeek-V3.2-Exp / inference/model.py
Pinned revision 87e509a2e5a1 ↗ · lines 560–564

Read code excerpt
        qr = self.q_norm(self.wq_a(x))
        q = self.wq_b(qr)
        q = q.view(bsz, seqlen, self.n_local_heads, self.qk_head_dim)
        q_nope, q_pe = torch.split(q, [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1)
        q_pe = apply_rotary_emb(q_pe, freqs_cis)

Contextual evidence from Rotate query part

Rotary embedding multiplies feature pairs by the coefficients; the indexer uses the non-interleaved layout.

apply-rope · deepseek-ai/DeepSeek-V3.2-Exp / inference/model.py
Pinned revision 87e509a2e5a1 ↗ · lines 405–425

Read code excerpt
def apply_rotary_emb(x: torch.Tensor, freqs_cis: torch.Tensor, interleaved: bool = True) -> torch.Tensor:
    """
    Applies rotary positional embeddings to the input tensor.

    Args:
        x (torch.Tensor): Input tensor with positional embeddings to be applied.
        freqs_cis (torch.Tensor): Precomputed complex exponential values for positional embeddings.

    Returns:
        torch.Tensor: Tensor with rotary embeddings applied.
    """
    dtype = x.dtype
    shape = x.shape
    if not interleaved:
        x = x.view(*shape[:-1], 2, -1).transpose(-1, -2).contiguous()
    x = torch.view_as_complex(x.float().view(*shape[:-1], -1, 2))
    freqs_cis = freqs_cis.view(1, x.size(1), 1, x.size(-1))
    y = torch.view_as_real(x * freqs_cis).flatten(3)
    if not interleaved:
        y = torch.cat([y[..., 0::2], y[..., 1::2]], dim=-1)
    return y.to(dtype)

Contextual evidence from Rotate query part

Rotary coefficients are precomputed once for the maximum sequence length, with YaRN frequency interpolation beyond the original 4,096 positions.

rope · deepseek-ai/DeepSeek-V3.2-Exp / inference/model.py
Pinned revision 87e509a2e5a1 ↗ · lines 334–402

Read code excerpt
    dim = args.qk_rope_head_dim
    seqlen = args.max_seq_len
    beta_fast = args.beta_fast
    beta_slow = args.beta_slow
    base = args.rope_theta
    factor = args.rope_factor

… lines 340–392 omitted …

    freqs = 1.0 / (base ** (torch.arange(0, dim, 2, dtype=torch.float32) / dim))
    if seqlen > args.original_seq_len:
        low, high = find_correction_range(beta_fast, beta_slow, dim, base, args.original_seq_len)
        smooth = 1 - linear_ramp_factor(low, high, dim // 2)
        freqs = freqs / factor * (1 - smooth) + freqs * smooth

    t = torch.arange(seqlen)
    freqs = torch.outer(t, freqs)
    freqs_cis = torch.polar(torch.ones_like(freqs), freqs)
    return freqs_cis