statsmodels is one of the slower steps in many statistics & survival workflows. AutoZyme ships a
verified, drop-in patch that is up to 25.2× faster, returning output within a strict, verified tolerance with no change to how you call it.
Best speedup25.2×
Median speedup23.4×
Output equivalenceTolerance
Best runtime baseline 3.31 min → optimized 8.29 s
Datasets5
Pass rate7/7
Benchmark charts
Switch benchmark platform; all charts update together
Platform
Speedup distribution
Each dot is one finalized dataset/thread run on Windows
log scale
glm_poisson_ood_corr_…
glm_poisson_ood_corr_dense · ood_large1 threads · 18.0× speedup4.80 min baseline → 17.95 s optimizedmemory 55 GB → 12 GBglm_poisson_ood_corr_dense · ood_large4 threads · 16.9× speedup3.22 min baseline → 11.35 s optimizedmemory 55 GB → 12 GBglm_poisson_ood_corr_dense · ood_large8 threads · 25.2× speedup3.31 min baseline → 8.29 s optimizedmemory 55 GB → 12 GB
25.2×
glm_poisson_medium
glm_poisson_medium · medium1 threads · 16.8× speedup3.01 min baseline → 10.73 s optimizedmemory 35 GB → 7.4 GBglm_poisson_medium · medium4 threads · 17.5× speedup2.40 min baseline → 9.28 s optimizedmemory 41 GB → 7.6 GBglm_poisson_medium · medium8 threads · 23.4× speedup2.33 min baseline → 5.98 s optimizedmemory 35 GB → 7.4 GB
23.4×
glm_poisson_tiny
glm_poisson_tiny · small1 threads · 21.6× speedup1.84 min baseline → 5.16 s optimizedmemory 19 GB → 4.1 GBglm_poisson_tiny · small4 threads · 23.2× speedup1.26 min baseline → 3.17 s optimizedmemory 19 GB → 3.3 GBglm_poisson_tiny · small8 threads · 17.2× speedup1.26 min baseline → 5.02 s optimizedmemory 19 GB → 4.1 GB
23.2×
glm_poisson_large
glm_poisson_large · large1 threads · 15.6× speedup4.53 min baseline → 18.50 s optimizedmemory 55 GB → 12 GBglm_poisson_large · large4 threads · 18.1× speedup3.29 min baseline → 10.96 s optimizedmemory 55 GB → 12 GBglm_poisson_large · large8 threads · 22.0× speedup3.32 min baseline → 9.01 s optimizedmemory 55 GB → 12 GB
22.0×
glm_poisson_ood_xlarge
glm_poisson_ood_xlarge · ood_xlarge1 threads · 14.4× speedup5.80 min baseline → 25.19 s optimizedmemory 76 GB → 16 GBglm_poisson_ood_xlarge · ood_xlarge4 threads · 14.7× speedup3.92 min baseline → 16.03 s optimizedmemory 76 GB → 16 GBglm_poisson_ood_xlarge · ood_xlarge8 threads · 17.6× speedup3.90 min baseline → 13.16 s optimizedmemory 76 GB → 16 GB
The public API stays the same; AutoZyme replaces only the supported fast path.
This task targets statsmodels.genmod.generalized_linear_model.GLM.fit in statsmodels. The benchmarked result
preserves the declared scientific output gate while reducing CPU runtime on the listed datasets.
Also searched as: GLM, generalized linear model, regression, logistic regression, poisson regression.
Supported scope
Fast Poisson/log-link IRLS path is gated by _can_fast_poisson_irls (__init__.py:135-173) and activates ONLY for: family is exactly sm.families.Poisson with sm.families.links.Log link (default); method='IRLS'; scale is None; cov_type='nonrobust'; cov_kwds is…Read full supported scope
Fast Poisson/log-link IRLS path is gated by _can_fast_poisson_irls (__init__.py:135-173) and activates ONLY for: family is exactly sm.families.Poisson with sm.families.links.Log link (default); method='IRLS'; scale is None; cov_type='nonrobust'; cov_kwds is None; kwargs attach_wls=False, wls_method='lstsq', tol_criterion='deviance', rtol in (0,0.0,None); _offset_exposure all-zero (no offset/exposure); freq_weights, var_weights, iweights, n_trials all all-ones (unit weights, no binomial trials); start_params either None or shape[0]==exog.shape[1]; and design matrix is FULL RANK (implicit — fast_minimal_wls_fit at :285-287 uses np.linalg.solve(wexog.T@wexog, wexog.T@wendog) normal equations, and fast_glm_initialize at :210-219 sets df_model=p-1 / df_resid=n-p directly, skipping the matrix_rank SVD). Convergence uses abs(dev[i-1]-dev[i])<=atol (atol=tol), which is mathematically identical to upstream _check_convergence's np.allclose(...,rtol=0) on the deviance criterion. fast_handle_constant (:179-200) assumes the first all-ones finite column (as produced by sm.add_constant) is the intercept. For the benchmarked default Poisson fit() the produced params/llf/scale/converged/n_iter match upstream within max_abs/rel_diff 1e-6 and rel_diff_llf 1e-8 (task.yaml metrics).
Out-of-scope behavior
silent fallback to upstream
Show detailed speedup table7 runs▾
Dataset
Tier
Platform
Threads
Baseline
Optimized
Speedup
Memory
Concordance
Pass
glm_poisson_large
large
Windows
8
3.32 min
9.01 s
22.0×
55.1 → 11.6 GB
—
pass
glm_poisson_medium
medium
Windows
8
2.33 min
5.98 s
23.4×
34.7 → 7.4 GB
—
pass
glm_poisson_ood_corr_dense
ood_large
Windows
8
3.31 min
8.29 s
25.2×
55.1 → 11.6 GB
—
pass
glm_poisson_ood_xlarge
ood_xlarge
Windows
8
3.90 min
13.16 s
17.6×
76.3 → 15.9 GB
—
pass
glm_poisson_tiny
small
Windows
4
1.26 min
3.17 s
23.2×
18.7 → 3.3 GB
—
pass
glm_poisson_medium
medium
macOS
1
1.85 min
3.21 s
34.4×
21.2 → 7.9 GB
—
pass
glm_poisson_tiny
small
macOS
1
57.73 s
1.60 s
35.6×
17.4 → 4.4 GB
—
pass
Frequently asked questions
Speeding up statsmodels
Why is statsmodels slow?
statsmodels is CPU-bound, and the stock implementation in statsmodels leaves performance on the table in its core numerical work. On the benchmark datasets the original takes 3.31 min where the AutoZyme path takes 8.29 s (25.2× faster).
How do I make statsmodels faster?
Install AutoZyme and activate the statsmodels patch, then keep using statsmodels exactly as before. AutoZyme transparently substitutes the faster, output-validated path, up to 25.2× faster on the benchmark datasets, with no pipeline or API changes.
Does the AutoZyme speedup change the statsmodels output?
Effectively no. The output is tolerance-equivalent: held within a frozen concordance gate (up to about 0.6% drift from the original statsmodels result) on every benchmark dataset.
How do I install the statsmodels speedup?
In Python: pip install autozyme, then import autozyme and autozyme.activate("statsmodels"). The patch applies automatically the next time you call statsmodels.genmod.generalized_linear_model.GLM.fit.