"""BBP floor v2 (generalized, measured-spectrum): production AMP semantics (bf16 block forwards, trainer-faithful) + NO structural noise assumption. Per layer & beta: signal spike = sigma1( mean_batches g_BP_fp32 ) noise edge = mean_batches sigma1( Xi_fluct ), Xi_fluct = (g_EP_amp - g_BP_fp32) - mean_batches(...) (systematic truncation bias = the batch-constant mean component -> distortion, removed; the fluctuation spectrum IS the detection noise, whatever its structure - generalized BBP/BGN) R(beta) = spike/edge; beta* = crossing of R=1 (log-interp); plus empirical u1-overlap vs beta. v1 (fp32, iid-additive fit) measured the wrong ensemble: fp32 rounding 2^-23 -> a=0 artifact. Production floor lives in bf16 (2^-8): RESULT 11 naive-cast death + amp-gate rising cos-vs-beta + quant beta-buyback are all BBP signatures. Old docstring below. Per-layer model g_hat(beta) = g_true + Xi/beta, Xi = EP-specific error (additive component). Measure across batches x betas: (i) entry-std s(beta) of (g_EP - g_BP), fit s = a/beta (+) b to split additive a (BBP-active) from multiplicative b (co-scaling, exempt per r-sweep); (ii) sigma1(g_BP) per layer; -> BBP/BGN threshold beta*_l = a_l*(sqrt(m)+sqrt(n))/2 / sigma1_l (iid-noise convention: bulk edge of Xi/beta at std nu=a/beta per entry is nu*(sqrt(m)+sqrt(n))/ sqrt(mn)*sqrt(mn)= a/beta*(sqrt m + sqrt n); spike detaches iff sigma1 > that /2..1 band — report both edge conventions); (iii) EMPIRICAL overlap cos(u1(g_hat), u1(g_BP)) vs beta — the BBP order parameter, compare its rise against beta*. Layers: per-block attn.qkv + ff.w2 (the two families), blocks 0..11.""" import argparse, pickle import numpy as np, torch, torch.nn as nn, torch.nn.functional as F from pathlib import Path ap = argparse.ArgumentParser() ap.add_argument('--ckpt', default='runs/fw72m_plain_s150000.pt') ap.add_argument('--K', type=int, default=3) ap.add_argument('--betas', default='1e-4,3e-4,1e-3,3e-3,1e-2') ap.add_argument('--nb', type=int, default=8) ap.add_argument('--qbits', type=int, default=6) a = ap.parse_args() dev = 'cuda' torch.manual_seed(11) B, T = 8, 256 class RMSNorm(nn.Module): def __init__(self, C, eps=1e-6): super().__init__(); self.g = nn.Parameter(torch.ones(C)); self.eps = eps def forward(self, x): return x * torch.rsqrt(x.pow(2).mean(-1, keepdim=True) + self.eps) * self.g class SwiGLU(nn.Module): def __init__(self, C): super().__init__() h = ((8 * C // 3) + 63) // 64 * 64 self.w1 = nn.Linear(C, h, bias=False); self.w3 = nn.Linear(C, h, bias=False) self.w2 = nn.Linear(h, C, bias=False) def forward(self, x): return self.w2(F.silu(self.w1(x)) * self.w3(x)) class Olmo2Attn(nn.Module): def __init__(self, C, H, T): super().__init__() self.H, self.hd = H, C // H self.qkv = nn.Linear(C, 3 * C, bias=False); self.proj = nn.Linear(C, C, bias=False) self.qn, self.kn = RMSNorm(C), RMSNorm(C) inv = 1.0 / (500000.0 ** (torch.arange(0, self.hd, 2).float() / self.hd)) fr = torch.outer(torch.arange(T).float(), inv) self.register_buffer('rc', fr.cos(), persistent=False) self.register_buffer('rs', fr.sin(), persistent=False) def rope(self, x): Tn = x.shape[2] x1, x2 = x[..., ::2], x[..., 1::2] c, s = self.rc[None, None, :Tn].to(x.dtype), self.rs[None, None, :Tn].to(x.dtype) return torch.stack((x1 * c - x2 * s, x1 * s + x2 * c), dim=-1).flatten(-2) def forward(self, x): Bn, Tn, C = x.shape q, k, v = self.qkv(x).split(C, dim=2) q, k = self.qn(q), self.kn(k) q = self.rope(q.view(Bn, Tn, self.H, self.hd).transpose(1, 2)) k = self.rope(k.view(Bn, Tn, self.H, self.hd).transpose(1, 2)) v = v.view(Bn, Tn, self.H, self.hd).transpose(1, 2) y = F.scaled_dot_product_attention(q, k, v, is_causal=True) return self.proj(y.transpose(1, 2).contiguous().view(Bn, Tn, C)) class Olmo2Block(nn.Module): def __init__(self, C, H, T): super().__init__() self.attn = Olmo2Attn(C, H, T); self.ff = SwiGLU(C) self.na, self.nf = RMSNorm(C), RMSNorm(C) def forward(self, z): z = z + self.na(self.attn(z)) return z + self.nf(self.ff(z)) ck = torch.load(a.ckpt, map_location='cpu', weights_only=False) cfg = ck['config']; C, H, L = cfg['C'], cfg['H'], cfg['L'] DD = Path('/home/yurenh2/ept/ep_run/data') / cfg.get('data', 'fineweb_edu') vocab = pickle.load(open(DD / 'meta.pkl', 'rb'))['vocab_size'] data = np.memmap(DD / 'val.bin', dtype=np.uint16, mode='r') tok = nn.Embedding(vocab, C).to(dev); tok.load_state_dict(ck['tok']) blocks = nn.ModuleList([Olmo2Block(C, H, T) for _ in range(L)]).to(dev) blocks.load_state_dict(ck['blocks'], strict=False) W_out = ck['wout'].to(dev) ln_f = RMSNorm(C).to(dev); ln_f.load_state_dict(ck['lnf']) NBT = B * T params = list(blocks.parameters()) qparams = None # set after qblocks exists names = [n for n, _ in blocks.named_parameters()] def readout(z): return ln_f(z) @ W_out.t() def get_batch(): ix = torch.randint(len(data) - T - 1, (B,)) x = torch.stack([torch.from_numpy(data[i:i + T].astype(np.int64)) for i in ix]) y = torch.stack([torch.from_numpy(data[i + 1:i + 1 + T].astype(np.int64)) for i in ix]) return x.to(dev), y.to(dev) def grads_from(outs_list, cots, plist=None): plist = plist if plist is not None else params obj = sum((o * c.detach()).sum() for o, c in zip(outs_list, cots)) gs = torch.autograd.grad(obj, plist, allow_unused=True, retain_graph=True) return [g.float() if g is not None else torch.zeros_like(p) for g, p in zip(gs, plist)] AMP = torch.autocast('cuda', dtype=torch.bfloat16) import copy qblocks = copy.deepcopy(blocks) if a.qbits > 0: with torch.no_grad(): for p in qblocks.parameters(): if p.dim() == 2: sc = p.abs().max() / (2 ** (a.qbits - 1) - 1) p.copy_(torch.round(p / sc) * sc) def ep_and_bp(x, y, beta): z = tok(x) zs_bp = [] for b in blocks: z = b(z); zs_bp.append(z) ce = F.cross_entropy(readout(zs_bp[-1]).reshape(-1, vocab), y.reshape(-1)) g_bp = [g.float() for g in torch.autograd.grad(ce, params, retain_graph=True, allow_unused=False)] f_ins, f_outs = [], [] prev = tok(x).detach() for b in qblocks: i = prev.detach().requires_grad_(True) with AMP: o = b(i) o = o.float() f_ins.append(i); f_outs.append(o) prev = o.detach() ins, outs = f_ins, f_outs zs = [o.detach().float() for o in f_outs] d = [None] * L for k in range(a.K): zc = zs[L - 1].detach().requires_grad_(True) ce_k = F.cross_entropy(readout(zc).reshape(-1, vocab), y.reshape(-1)) d[L - 1] = (-beta * NBT * torch.autograd.grad(ce_k, zc)[0]).detach().float() for l in range(L - 2, -1, -1): d[l] = torch.autograd.grad(outs[l + 1], ins[l + 1], grad_outputs=d[l + 1], retain_graph=True)[0].detach().float() prev = tok(x).detach() n_ins, n_outs = [], [] for l in range(L): i = prev.detach().requires_grad_(True) with AMP: o = qblocks[l](i) o = o.float() n_ins.append(i); n_outs.append(o) zs[l] = o.detach().float() + d[l] prev = zs[l] ins, outs = n_ins, n_outs md = [-di / (beta * NBT) for di in d] # normalize so EP grad is on BP scale g_ep = grads_from(outs, md, list(qblocks.parameters())) return g_bp, g_ep SEL = [i for i, n in enumerate(names) if n.endswith('attn.qkv.weight') or n.endswith('ff.w2.weight')] SEL = [i for i in SEL if int(names[i].split('.')[0]) in (0, 6, 8, 11)] betas = [float(s) for s in a.betas.split(',')] batches = [get_batch() for _ in range(a.nb)] # pass 1: per batch/beta store g_ep; per batch store g_bp (fp32 reference) store_ep = {i: {b: [] for b in betas} for i in SEL} store_bp = {i: [] for i in SEL} for (x, y) in batches: for bi, b in enumerate(betas): g_bp, g_ep = ep_and_bp(x, y, b) for i in SEL: store_ep[i][b].append(g_ep[i].detach().cpu()) if bi == 0: store_bp[i].append(g_bp[i].detach().cpu()) del g_bp, g_ep torch.cuda.empty_cache() print('layer m x n spike=s1(gbar) ' + ' '.join(f'R@{b:g}(ov)' for b in betas) + ' beta*(R=1)', flush=True) for i in SEL: m, n = params[i].shape gbar = torch.stack(store_bp[i]).mean(0) s1 = float(torch.linalg.svdvals(gbar)[0]) u1 = torch.linalg.svd(gbar, full_matrices=False).U[:, 0] Rs, cells = [], [] for b in betas: Xi = torch.stack([ge - gb for ge, gb in zip(store_ep[i][b], store_bp[i])]) Xif = Xi - Xi.mean(0, keepdim=True) edge = float(np.mean([torch.linalg.svdvals(Xif[j])[0] for j in range(Xif.shape[0])])) R = s1 / max(edge, 1e-30) ovs = [abs(float(u1 @ torch.linalg.svd(ge, full_matrices=False).U[:, 0])) for ge in store_ep[i][b]] Rs.append(R); cells.append(f'{R:8.2f}({np.mean(ovs):.3f})') bstar = float('nan') lb = np.log(np.array(betas)); lR = np.log(np.maximum(Rs, 1e-12)) for j in range(len(betas) - 1): if (lR[j] - 0.0) * (lR[j + 1] - 0.0) <= 0 and lR[j] != lR[j + 1]: t = (0.0 - lR[j]) / (lR[j + 1] - lR[j]); bstar = float(np.exp(lb[j] + t * (lb[j + 1] - lb[j]))); break print(f'{names[i]:22s} {m:5d}x{n:<5d} {s1:12.4g} ' + ' '.join(cells) + f' {bstar:.2e}' if bstar == bstar else f'{names[i]:22s} {m:5d}x{n:<5d} {s1:12.4g} ' + ' '.join(cells) + ' R>1 everywhere', flush=True) print('BBP2Q_DONE', flush=True)