คู่มือการใช้ NVIDIA cuML และ RAPIDS เพื่อเร่งความเร็ว Machine Learning ด้วย GPU

import os
import sys
import time
import json
import shutil
import warnings
import subprocess
import importlib
import traceback
warnings.filterwarnings("ignore")
QUICK = False
SEED = 42
SCALE = 0.25 if QUICK else 1.0
N_MAIN = int(200_000 * SCALE)
D_MAIN = 64
N_RF = int(50_000 * SCALE)
D_RF = 32
N_NN_INDEX = int(50_000 * SCALE)
N_NN_QUERY = int(5_000 * SCALE)
N_DBSCAN = int(20_000 * SCALE)
N_MANIFOLD = int(60_000 * SCALE)
N_ACCEL = int(80_000 * SCALE)
RESULTS = []
NOTES = []
def banner(title):
line = "=" * 78
print(f"\n{line}\n {title}\n{line}", flush=True)
def section(title, fn, *args, **kwargs):
banner(title)
t0 = time.perf_counter()
try:
fn(*args, **kwargs)
except Exception:
print(f"[!] Section skipped due to an error:\n{traceback.format_exc()}")
print(f"[section wall time: {time.perf_counter() - t0:.1f}s]", flush=True)
def bootstrap():
if shutil.which("nvidia-smi") is None:
raise SystemExit(
"No NVIDIA GPU found. In Colab: Runtime > Change runtime type > GPU."
)
print(subprocess.run(
["nvidia-smi",
"--query-gpu=name,memory.total,compute_cap,driver_version",
"--format=csv"],
capture_output=True, text=True).stdout)
try:
import cuml
print("cuML already available — skipping install.")
except ImportError:
print("Installing RAPIDS cuML (this takes ~1-3 minutes)...")
pin = ""
try:
import cudf
major_minor = ".".join(cudf.__version__.split("+")[0].split(".")[:2])
pin = f"=={major_minor}.*"
print(f" Pinning to the preinstalled cuDF line: cuml-cu12{pin}")
except Exception:
print(" cuDF not found; installing the latest stable cuml-cu12.")
cmd = [sys.executable, "-m", "pip", "install", "-q",
"--extra-index-url=https://pypi.nvidia.com", f"cuml-cu12{pin}"]
print("$ " + " ".join(cmd))
rc = subprocess.run(cmd).returncode
if rc != 0:
raise SystemExit(
"pip install failed. Alternative that always works on Colab:\n"
" !git clone https://github.com/rapidsai/rapidsai-csp-utils.git\n"
" !python rapidsai-csp-utils/colab/pip-install.py"
)
importlib.invalidate_caches()
import cuml
import cupy
print(f"cuml {cuml.__version__}")
print(f"cupy {cupy.__version__}")
try:
import cudf
print(f"cudf {cudf.__version__}")
except Exception:
pass
import sklearn
print(f"sklearn {sklearn.__version__} (cuML requires scikit-learn >= 1.6)")
bootstrap()
import numpy as np
import cupy as cp
import cuml
import matplotlib.pyplot as plt
from cuml.datasets import make_classification as gpu_make_classification
from cuml.datasets import make_blobs as gpu_make_blobs
rng = np.random.RandomState(SEED)
cp.random.seed(SEED)
class Timer:
def __init__(self, label, sync=True):
self.label = label
self.sync = sync
def __enter__(self):
if self.sync:
cp.cuda.runtime.deviceSynchronize()
self.t0 = time.perf_counter()
return self
def __exit__(self, *exc):
if self.sync:
cp.cuda.runtime.deviceSynchronize()
self.dt = time.perf_counter() - self.t0
print(f" {self.label:<44s} {self.dt:8.3f}s")
return False
def to_numpy(a):
if isinstance(a, cp.ndarray):
return cp.asnumpy(a)
if hasattr(a, "to_numpy"):
return a.to_numpy()
return np.asarray(a)
def record(task, cpu_s, gpu_s):
RESULTS.append((task, cpu_s, gpu_s))
if cpu_s and gpu_s:
print(f" -> {task}: {cpu_s / gpu_s:.1f}x speedup\n")
ACCEL_SCRIPT = f'''
import time
import numpy as np
from sklearn.datasets import make_blobs
from sklearn.decomposition import PCA
from sklearn.cluster import KMeans
from sklearn.neighbors import NearestNeighbors
from sklearn.linear_model import Ridge
X, y = make_blobs(n_samples={N_ACCEL}, n_features=32, centers=12, random_state=0)
X = X.astype("float32"); y = y.astype("float32")
t0 = time.perf_counter()
PCA(n_components=8).fit_transform(X)
KMeans(n_clusters=12, n_init=1, random_state=0).fit(X)
NearestNeighbors(n_neighbors=8).fit(X[:{N_ACCEL // 2}]).kneighbors(X[:5000])
Ridge(alpha=1.0).fit(X, y)
Ridge(alpha=1.0, positive=True).fit(X[:5000], y[:5000])
print("MODELTIME %.3f" % (time.perf_counter() - t0))
'''
def demo_accel():
path = "/content/_accel_demo.py" if os.path.isdir("/content") else "_accel_demo.py"
with open(path, "w") as f:
f.write(ACCEL_SCRIPT)
def run(cmd, label):
print(f"\n$ {' '.join(cmd[1:])}")
t0 = time.perf_counter()
p = subprocess.run(cmd, capture_output=True, text=True)
wall = time.perf_counter() - t0
out = p.stdout + p.stderr
model_s = None
for line in out.splitlines():
if line.startswith("MODELTIME"):
model_s = float(line.split()[1])
print(out.strip()[:4000])
print(f"[{label}] model time = {model_s}s | process wall = {wall:.1f}s")
return model_s
cpu_s = run([sys.executable, path], "stock sklearn")
cmd = [sys.executable, "-m", "cuml.accel", "--profile", path]
gpu_s = run(cmd, "cuml.accel")
if gpu_s is None:
gpu_s = run([sys.executable, "-m", "cuml.accel", path], "cuml.accel")
record("cuml.accel (sklearn script, unmodified)", cpu_s, gpu_s)
NOTES.append(
"cuml.accel needed ZERO source changes; the profile table above shows "
"which calls ran on GPU and why Ridge(positive=True) fell back to CPU."
)

def demo_native_api():
from cuml.preprocessing import StandardScaler
from cuml.model_selection import train_test_split
X, y = gpu_make_blobs(n_samples=50_000, n_features=8, centers=5,
random_state=SEED, dtype=np.float32)
print(f"cuml.datasets output lives on device: {type(X).__module__}, "
f"shape={X.shape}, dtype={X.dtype}")
try:
import cudf
df = cudf.DataFrame(X, columns=[f"f{i}" for i in range(X.shape[1])])
back = df.values
ptr_a = X.__cuda_array_interface__["data"][0]
ptr_b = back.__cuda_array_interface__["data"][0]
print(f"CuPy ptr = {hex(ptr_a)}")
print(f"cuDF->CuPy= {hex(ptr_b)}")
print("Same device pointer (true zero-copy)? ", ptr_a == ptr_b)
print("Note: a column-major DataFrame round trip may re-pack; what "
"matters is that no host (CPU) round trip ever happens.")
scaled = StandardScaler().fit_transform(df)
print(f"StandardScaler(cuDF) -> {type(scaled).__name__}")
except Exception as e:
print(f"cuDF interop skipped: {e}")
from cuml.decomposition import PCA
pca = PCA(n_components=3).fit(X)
print(f"default (mirrors input) -> {type(pca.transform(X)).__name__}")
with cuml.using_output_type("numpy"):
print(f"inside using_output_type() -> {type(pca.transform(X)).__name__}")
print(f"after the context manager -> {type(pca.transform(X)).__name__}")
NOTES.append(
"Keep output_type as CuPy/cuDF inside a pipeline; converting to NumPy "
"on every step forces a device->host copy and eats the speedup."
)
Xtr, Xte, ytr, yte = train_test_split(X, y, test_size=0.2, random_state=SEED)
print(f"train_test_split -> {Xtr.shape} / {Xte.shape}, still on device: "
f"{isinstance(Xtr, cp.ndarray)}")

def demo_benchmarks():
from sklearn.decomposition import PCA as skPCA
from sklearn.cluster import KMeans as skKMeans, DBSCAN as skDBSCAN
from sklearn.neighbors import NearestNeighbors as skNN
from sklearn.linear_model import LogisticRegression as skLR
from sklearn.ensemble import RandomForestClassifier as skRF
from cuml.decomposition import PCA as cuPCA
from cuml.cluster import KMeans as cuKMeans, DBSCAN as cuDBSCAN
from cuml.neighbors import NearestNeighbors as cuNN
from cuml.linear_model import LogisticRegression as cuLR
from cuml.ensemble import RandomForestClassifier as cuRF
print(f"Generating {N_MAIN:,} x {D_MAIN} on the GPU...")
Xg, yg = gpu_make_classification(n_samples=N_MAIN, n_features=D_MAIN,
n_informative=32, n_classes=4,
random_state=SEED)
Xg = Xg.astype(cp.float32)
yg = yg.astype(cp.int32)
Xc, yc = cp.asnumpy(Xg), cp.asnumpy(yg)
print(f" device array: {Xg.nbytes / 1e6:.0f} MB\n")
print("PCA (n_components=16)")
with Timer("sklearn", sync=False) as t:
skPCA(n_components=16, random_state=SEED).fit_transform(Xc)
cpu = t.dt
with Timer("cuML") as t:
cuPCA(n_components=16, random_state=SEED).fit_transform(Xg)
record("PCA", cpu, t.dt)
print("KMeans (k=16)")
with Timer("sklearn", sync=False) as t:
skKMeans(n_clusters=16, n_init=1, max_iter=100,
random_state=SEED).fit(Xc)
cpu = t.dt
with Timer("cuML") as t:
cuKMeans(n_clusters=16, n_init=1, max_iter=100,
random_state=SEED).fit(Xg)
record("KMeans", cpu, t.dt)
print(f"NearestNeighbors k=16 ({N_NN_INDEX:,} index / {N_NN_QUERY:,} query)")
idx_g, q_g = Xg[:N_NN_INDEX], Xg[N_NN_INDEX:N_NN_INDEX + N_NN_QUERY]
idx_c, q_c = cp.asnumpy(idx_g), cp.asnumpy(q_g)
with Timer("sklearn (brute)", sync=False) as t:
skNN(n_neighbors=16, algorithm="brute", n_jobs=-1).fit(idx_c).kneighbors(q_c)
cpu = t.dt
with Timer("cuML") as t:
d_gpu, i_gpu = cuNN(n_neighbors=16).fit(idx_g).kneighbors(q_g)
record("NearestNeighbors", cpu, t.dt)
print("LogisticRegression (multinomial, lbfgs/QN)")
with Timer("sklearn", sync=False) as t:
sk_lr = skLR(max_iter=200, n_jobs=-1).fit(Xc, yc)
cpu = t.dt
with Timer("cuML") as t:
cu_lr = cuLR(max_iter=200).fit(Xg, yg)
record("LogisticRegression", cpu, t.dt)
print(f" accuracy sklearn={sk_lr.score(Xc, yc):.4f} "
f"cuML={float((cu_lr.predict(Xg) == yg).mean()):.4f} "
"(different solvers, so small differences are expected)\n")
print(f"RandomForestClassifier (100 trees, depth 12, {N_RF:,} x {D_RF})")
Xr_g, yr_g = gpu_make_classification(n_samples=N_RF, n_features=D_RF,
n_informative=16, n_classes=2,
random_state=SEED)
Xr_g = Xr_g.astype(cp.float32)
yr_g = yr_g.astype(cp.int32)
Xr_c, yr_c = cp.asnumpy(Xr_g), cp.asnumpy(yr_g)
with Timer("sklearn", sync=False) as t:
skRF(n_estimators=100, max_depth=12, n_jobs=-1,
random_state=SEED).fit(Xr_c, yr_c)
cpu = t.dt
with Timer("cuML") as t:
cu_rf = cuRF(n_estimators=100, max_depth=12, n_bins=128,
n_streams=4, random_state=SEED).fit(Xr_g, yr_g)
record("RandomForest (fit)", cpu, t.dt)
globals()["_RF_ARTIFACTS"] = (cu_rf, Xr_g, yr_g, Xr_c, yr_c)
print(f"DBSCAN ({N_DBSCAN:,} x 8)")
Xd_g, _ = gpu_make_blobs(n_samples=N_DBSCAN, n_features=8, centers=6,
cluster_std=0.6, random_state=SEED,
dtype=np.float32)
Xd_c = cp.asnumpy(Xd_g)
with Timer("sklearn", sync=False) as t:
lab_c = skDBSCAN(eps=0.9, min_samples=8, n_jobs=-1).fit_predict(Xd_c)
cpu = t.dt
with Timer("cuML") as t:
lab_g = cuDBSCAN(eps=0.9, min_samples=8).fit_predict(Xd_g)
record("DBSCAN", cpu, t.dt)
print(f" clusters found: sklearn={len(set(lab_c.tolist())) - 1}, "
f"cuML={len(set(cp.asnumpy(lab_g).tolist())) - 1}\n")

def demo_manifold():
from cuml.manifold import UMAP, TSNE
from cuml.metrics import trustworthiness
X, y = gpu_make_blobs(n_samples=N_MANIFOLD, n_features=48, centers=8,
cluster_std=1.6, random_state=SEED, dtype=np.float32)
print(f"data: {X.shape}")
embeddings = {}
for n_neighbors, min_dist in [(15, 0.1), (50, 0.0)]:
key = f"UMAP(n_neighbors={n_neighbors}, min_dist={min_dist})"
with Timer(key) as t:
emb = UMAP(n_neighbors=n_neighbors, min_dist=min_dist,
n_components=2, random_state=SEED).fit_transform(X)
sub = slice(0, min(5000, X.shape[0]))
tw = trustworthiness(X[sub], emb[sub], n_neighbors=10)
print(f" trustworthiness = {tw:.4f}")
embeddings[key] = (emb, t.dt, tw)
with Timer("TSNE(method='fft')") as t:
tsne_emb = TSNE(n_components=2, perplexity=30,
random_state=SEED).fit_transform(X)
embeddings["TSNE"] = (tsne_emb, t.dt, float("nan"))
best_key = max([k for k in embeddings if k.startswith("UMAP")],
key=lambda k: embeddings[k][2])
emb = embeddings[best_key][0]
print(f"\nClustering the '{best_key}' embedding with GPU HDBSCAN")
try:
from cuml.cluster import HDBSCAN
with Timer("HDBSCAN") as t:
hdb = HDBSCAN(min_cluster_size=max(int(50 * SCALE), 5),
min_samples=10, prediction_data=True).fit(emb)
labels = cp.asarray(hdb.labels_)
n_clusters = int(labels.max()) + 1
noise = float((labels == -1).mean())
print(f" clusters={n_clusters} noise fraction={noise:.3f}")
try:
from cuml.metrics.cluster import adjusted_rand_score
print(f" adjusted Rand index vs ground truth: "
f"{adjusted_rand_score(y, labels):.4f}")
except Exception as e:
print(f" ARI skipped: {e}")
try:
from cuml.cluster.hdbscan import all_points_membership_vectors
mv = all_points_membership_vectors(hdb)
print(f" soft-cluster membership matrix: {tuple(mv.shape)}")
except Exception as e:
print(f" soft clustering skipped: {e}")
except Exception as e:
print(f" HDBSCAN step skipped: {e}")
fig, axes = plt.subplots(1, 3, figsize=(16, 5))
keys = list(embeddings)[:3]
for ax, k in zip(axes, keys):
e = to_numpy(embeddings[k][0])
c = to_numpy(y)
ax.scatter(e[:, 0], e[:, 1], c=c, s=1.5, cmap="tab10", alpha=0.6)
ax.set_title(f"{k}\n{embeddings[k][1]:.2f}s", fontsize=9)
ax.set_xticks([]); ax.set_yticks([])
plt.suptitle("GPU manifold learning (colored by ground-truth cluster)")
plt.tight_layout(); plt.show()

def demo_fil():
from sklearn.ensemble import RandomForestClassifier as skRF
n = int(30_000 * SCALE)
Xg, yg = gpu_make_classification(n_samples=n, n_features=24,
n_informative=12, n_classes=2,
random_state=SEED)
Xg = Xg.astype(cp.float32)
Xc, yc = cp.asnumpy(Xg), cp.asnumpy(yg.astype(cp.int32))
print("Training a 200-tree sklearn forest on CPU (the model to be served)...)")
sk_model = skRF(n_estimators=200, max_depth=10, n_jobs=-1,
random_state=SEED).fit(Xc, yc)
with Timer("sklearn.predict_proba (CPU)", sync=False) as t:
p_cpu = sk_model.predict_proba(Xc)[:, 1]
cpu = t.dt
fil = None
try:
from cuml.fil import ForestInference
except Exception as e:
print(f"cuml.fil unavailable on this build ({e}); skipping. "
"On newer stacks use the standalone nvForest library instead.")
return
for kwargs in ({"is_classifier": True, "output_type": "numpy"},
{"output_class": True, "output_type": "numpy"},
{}):
try:
fil = ForestInference.load_from_sklearn(sk_model, **kwargs)
print(f"Loaded into FIL with kwargs={kwargs or '{}'}")
break
except Exception as e:
print(f" load_from_sklearn(**{kwargs}) -> {type(e).__name__}: {e}")
if fil is None:
print("Could not load the forest into FIL on this build; skipping.")
return
try:
fil.optimize(batch_size=Xg.shape[0])
print("Ran fil.optimize() to auto-tune layout/chunk size for this batch.")
except Exception:
pass
fil.predict_proba(Xg[:1024])
with Timer("FIL predict_proba (GPU)") as t:
p_gpu = fil.predict_proba(Xg)
record("Forest inference (200 trees)", cpu, t.dt)
p_gpu = to_numpy(p_gpu)
p_gpu = p_gpu[:, 1] if p_gpu.ndim == 2 and p_gpu.shape[1] == 2 else p_gpu.ravel()
print(f" max |prob difference| vs sklearn: {np.abs(p_gpu - p_cpu).max():.2e} "
"(FIL defaults to float32, so ~1e-6 is normal)")
NOTES.append(
"FIL/nvForest is the piece that matters in production: the same trained "
"artifact, served with GPU-class throughput and no retraining."
)

def demo_explainer():
from cuml.linear_model import Ridge
from cuml.explainer import PermutationExplainer
n, d = int(20_000 * SCALE), 12
X = cp.asarray(rng.randn(n, d), dtype=cp.float32)
true_coef = cp.asarray(rng.uniform(-3, 3, size=d), dtype=cp.float32)
y = (X @ true_coef + 0.1 * cp.asarray(rng.randn(n), dtype=cp.float32))
model = Ridge(alpha=1e-3).fit(X, y)
coef = cp.asarray(model.coef_).ravel()
background = X[:200]
to_explain = X[200:220]
with Timer("PermutationExplainer (GPU)") as t:
expl = PermutationExplainer(model=model.predict, data=background,
random_state=SEED)
shap_values = expl.shap_values(to_explain)
shap_values = cp.asarray(shap_values)
analytic = (to_explain - background.mean(axis=0)) * coef
err = float(cp.abs(shap_values - analytic).max())
print(f" max |SHAP - analytical linear SHAP| = {err:.4f}")
print(" (permutation SHAP is sampling-based, so a small residual is "
"expected; the pattern must match)")
base = float(model.predict(background).mean())
recon = cp.asarray(shap_values).sum(axis=1) + base
actual = cp.asarray(model.predict(to_explain)).ravel()
print(f" additivity residual (mean |sum(phi)+base - f(x)|) = "
f"{float(cp.abs(recon - actual).mean()):.4f}")
imp = to_numpy(cp.abs(shap_values).mean(axis=0))
order = np.argsort(imp)[::-1]
plt.figure(figsize=(8, 3.5))
plt.bar(range(d), imp[order], color="#76b900")
plt.xticks(range(d), [f"f{i}" for i in order])
plt.ylabel("mean |SHAP|")
plt.title("GPU SHAP feature importance (cuml.explainer.PermutationExplainer)")
plt.tight_layout(); plt.show()
def demo_hpo():
from sklearn.model_selection import RandomizedSearchCV
from cuml.ensemble import RandomForestClassifier as cuRF
n = int(60_000 * SCALE)
X, y = gpu_make_classification(n_samples=n, n_features=24, n_informative=14,
n_classes=3, random_state=SEED)
X = cp.asnumpy(X.astype(cp.float32))
y = cp.asnumpy(y.astype(cp.int32))
param_dist = {
"n_estimators": [50, 100, 200],
"max_depth": [8, 12, 16],
"max_features": [0.3, 0.5, 0.8],
"n_bins": [64, 128, 256],
}
search = RandomizedSearchCV(
cuRF(random_state=SEED, n_streams=1),
param_distributions=param_dist,
n_iter=8, cv=3, n_jobs=1, random_state=SEED, verbose=0,
)
with Timer("RandomizedSearchCV over cuML RF (8 x 3 fits)", sync=True) as t:
search.fit(X, y)
print(f" best CV accuracy: {search.best_score_:.4f}")
print(f" best params : {json.dumps(search.best_params_)}")
NOTES.append(
"Because each fit is seconds instead of minutes, you can afford a real "
"search space instead of one hand-tuned guess."
)

def demo_persistence():
import pickle
art = globals().get("_RF_ARTIFACTS")
if art is None:
from cuml.ensemble import RandomForestClassifier as cuRF
Xg, yg = gpu_make_classification(n_samples=int(20_000 * SCALE),
n_features=16, n_classes=2,
random_state=SEED)
Xg = Xg.astype(cp.float32); yg = yg.astype(cp.int32)
model = cuRF(n_estimators=50, max_depth=10, random_state=SEED).fit(Xg, yg)
else:
model, Xg, yg, _, _ = art
before = to_numpy(model.predict(Xg[:1000]))
path = "/content/cuml_rf.pkl" if os.path.isdir("/content") else "cuml_rf.pkl"
with open(path, "wb") as f:
pickle.dump(model, f)
size_mb = os.path.getsize(path) / 1e6
with open(path, "rb") as f:
restored = pickle.load(f)
after = to_numpy(restored.predict(Xg[:1000]))
print(f" pickled model: {size_mb:.2f} MB at {path}")
print(f" predictions identical after round trip: {np.array_equal(before, after)}")
print(" cuML uses cloudpickle internally, so models trained under "
"cuml.accel can be loaded and used by plain scikit-learn on a "
"CPU-only machine.")
print(" SECURITY: never unpickle a model file from an untrusted source.")
def demo_summary():
rows = [(t, c, g) for (t, c, g) in RESULTS if c and g]
if not rows:
print("No comparable timings were collected.")
return
w = max(len(r[0]) for r in rows)
print(f"{'task'.ljust(w)} {'CPU (s)':>9} {'GPU (s)':>9} {'speedup':>9}")
print("-" * (w + 32))
for t, c, g in rows:
print(f"{t.ljust(w)} {c:9.3f} {g:9.3f} {c / g:8.1f}x")
labels = [r[0] for r in rows][::-1]
speeds = [r[1] / r[2] for r in rows][::-1]
plt.figure(figsize=(9, 0.55 * len(labels) + 2))
bars = plt.barh(labels, speeds, color="#76b900")
for b, s in zip(bars, speeds):
plt.text(b.get_width() * 1.02, b.get_y() + b.get_height() / 2,
f"{s:.1f}x", va="center", fontsize=9)
plt.axvline(1.0, color="grey", ls="--", lw=1)
plt.xscale("log")
plt.xlabel("speedup vs CPU (log scale, higher is better)")
plt.title(f"cuML {cuml.__version__} on this Colab GPU")
plt.tight_layout(); plt.show()
print("\nTakeaways")
for i, n in enumerate(NOTES, 1):
print(f" {i}. {n}")
print("""
Caveats worth internalizing:
* Speedups are size-dependent. Under ~10k rows, PCIe transfer and kernel
launch overhead usually dominate, and the CPU wins. Benchmark YOUR shapes.
* Always deviceSynchronize() before stopping a timer, or you time nothing.
* cuML matches scikit-learn's API, not its exact numerics: different solvers,
float32 defaults, and non-deterministic reductions produce small deltas.
* Multi-GPU / multi-node: swap cuml.X for cuml.dask.X with a LocalCUDACluster.
Where to go next:
* cuml.accel compatibility matrix : https://docs.nvidia.com/cuml/stable/cuml-accel/compatibility/
* Profiling accelerated code : %%cuml.accel.profile and %%cuml.accel.line_profile
* Multi-GPU guide : https://docs.nvidia.com/cuml/stable/dask_multigpu_guide/
* Walkthrough notebooks : https://github.com/NVIDIA/cuml/tree/main/notebooks
""")
_t_all = time.perf_counter()
section("1. cuml.accel — zero code change acceleration of stock scikit-learn",
demo_accel)
section("2. Native cuML API: cuDF/CuPy interop, zero-copy, output types",
demo_native_api)
section("3. CPU vs GPU benchmark harness", demo_benchmarks)
section("4. UMAP -> trustworthiness -> HDBSCAN pipeline", demo_manifold)
section("5. High-throughput forest inference (FIL / nvForest)", demo_fil)
section("6. GPU SHAP with cuml.explainer, validated analytically", demo_explainer)
section("7. Hyperparameter search over cuML estimators", demo_hpo)
section("8. Serialization and GPU -> CPU portability", demo_persistence)
section("9. Summary", demo_summary)
print(f"\nTotal tutorial wall time: {time.perf_counter() - _t_all:.1f}s")