diff --git a/.github/workflows/checks.yaml b/.github/workflows/checks.yaml
index 258935d2b..81027df03 100644
--- a/.github/workflows/checks.yaml
+++ b/.github/workflows/checks.yaml
@@ -50,7 +50,7 @@ jobs:
         run: uv run ruff format .
 
       - name: Run tests
-        run: uv run pytest tests/ --runslow --durations 10 --numprocesses auto
+        run: uv run pytest tests/ --runslow --durations 20 --numprocesses auto --dist worksteal
         env:
           WANDB_API_KEY: ${{ secrets.WANDB_API_KEY }}
           OMPI_ALLOW_RUN_AS_ROOT: 1
diff --git a/spd/clustering/merge_run_config.py b/spd/clustering/merge_run_config.py
index feba16967..d86cbc7a6 100644
--- a/spd/clustering/merge_run_config.py
+++ b/spd/clustering/merge_run_config.py
@@ -71,7 +71,7 @@ class ClusteringRunConfig(BaseModel):
     """Configuration for a complete merge clustering run.
 
     Extends MergeConfig with parameters for model, dataset, and batch configuration.
-    CLI parameters (base_path, devices, workers_per_device) have defaults but will always be overridden
+    CLI parameters (base_path, devices, workers_per_device, dataset_streaming) have defaults but will always be overridden
     """
 
     merge_config: MergeConfig = Field(
@@ -100,6 +100,10 @@ class ClusteringRunConfig(BaseModel):
         default="perm_invariant_hamming",
         description="Method to use for computing distances between clusterings",
     )
+    dataset_streaming: bool = Field(
+        default=False,
+        description="Whether to use streaming dataset loading (if supported by the dataset). see https://github.com/goodfire-ai/spd/pull/199",
+    )
 
     # Implementation details
     # note that these are *always* overriden by CLI args in `spd/clustering/scripts/main.py`, but we have to have defaults here
@@ -161,6 +165,15 @@ def validate_intervals(self) -> Self:
 
         return self
 
+    @model_validator(mode="after")
+    def validate_streaming_compatibility(self) -> Self:
+        """Ensure dataset_streaming is only enabled for compatible tasks."""
+        if self.dataset_streaming and self.task_name != "lm":
+            raise ValueError(
+                f"Streaming dataset loading only supported for 'lm' task, got '{self.task_name}'"
+            )
+        return self
+
     @property
     def wandb_decomp_model(self) -> str:
         """Extract the WandB run ID of the source decomposition from the model_path
diff --git a/spd/clustering/pipeline/clustering_pipeline.py b/spd/clustering/pipeline/clustering_pipeline.py
index 1e07c71d7..8c6b72f9d 100644
--- a/spd/clustering/pipeline/clustering_pipeline.py
+++ b/spd/clustering/pipeline/clustering_pipeline.py
@@ -46,9 +46,21 @@ def main(config: ClusteringRunConfig) -> None:
 
     # Split dataset into batches
     logger.info(f"Splitting dataset into {config.n_batches} batches...")
+    split_dataset_kwargs: dict[str, Any] = dict()
+    if config.dataset_streaming:
+        logger.info("Using streaming dataset loading")
+        split_dataset_kwargs["config_kwargs"] = dict(streaming=True)
+        # check this here as well as the model validator because we edit `config.dataset_streaming` after init in main() after the CLI args are parsed
+        # not sure if this is actually a problem though
+        assert config.task_name == "lm", (
+            f"Streaming dataset loading only supported for 'lm' task, got '{config.task_name = }'. Remove dataset_streaming=True from config or use a different task."
+        )
     batches: Iterator[BatchTensor]
     dataset_config: dict[str, Any]
-    batches, dataset_config = split_dataset(config=config)
+    batches, dataset_config = split_dataset(
+        config=config,
+        **split_dataset_kwargs,
+    )
     storage.save_batches(batches=batches, config=dataset_config)
     batch_paths: list[Path] = storage.get_batch_paths()
     n_batch_paths: int = len(batch_paths)
diff --git a/spd/clustering/pipeline/s1_split_dataset.py b/spd/clustering/pipeline/s1_split_dataset.py
index d5427e600..711cda65a 100644
--- a/spd/clustering/pipeline/s1_split_dataset.py
+++ b/spd/clustering/pipeline/s1_split_dataset.py
@@ -21,7 +21,10 @@
 from spd.models.component_model import ComponentModel, SPDRunInfo
 
 
-def split_dataset(config: ClusteringRunConfig) -> tuple[Iterator[BatchTensor], dict[str, Any]]:
+def split_dataset(
+    config: ClusteringRunConfig,
+    **kwargs: Any,
+) -> tuple[Iterator[BatchTensor], dict[str, Any]]:
     """Split a dataset into n_batches of batch_size, returning iterator and config"""
     ds: Generator[BatchTensor, None, None]
     ds_config_dict: dict[str, Any]
@@ -30,11 +33,13 @@ def split_dataset(config: ClusteringRunConfig) -> tuple[Iterator[BatchTensor], d
             ds, ds_config_dict = _get_dataloader_lm(
                 model_path=config.model_path,
                 batch_size=config.batch_size,
+                **kwargs,
             )
         case "resid_mlp":
             ds, ds_config_dict = _get_dataloader_resid_mlp(
                 model_path=config.model_path,
                 batch_size=config.batch_size,
+                **kwargs,
             )
         case name:
             raise ValueError(
@@ -56,6 +61,7 @@ def limited_iterator() -> Iterator[BatchTensor]:
 def _get_dataloader_lm(
     model_path: str,
     batch_size: int,
+    config_kwargs: dict[str, Any] | None = None,
 ) -> tuple[Generator[BatchTensor, None, None], dict[str, Any]]:
     """split up a SS dataset into n_batches of batch_size, returned the saved paths
 
@@ -81,15 +87,22 @@ def _get_dataloader_lm(
             f"Expected task_config to be of type LMTaskConfig since using `_get_dataloader_lm`, but got {type(cfg.task_config) = }"
         )
 
+        config_kwargs_: dict[str, Any] = {
+            **dict(
+                is_tokenized=False,
+                streaming=False,
+                seed=0,
+            ),
+            **(config_kwargs or {}),
+        }
+
         dataset_config: DatasetConfig = DatasetConfig(
             name=cfg.task_config.dataset_name,
             hf_tokenizer_path=pretrained_model_name,
             split=cfg.task_config.train_data_split,
             n_ctx=cfg.task_config.max_seq_len,
-            is_tokenized=False,
-            streaming=False,
-            seed=0,
             column_name=cfg.task_config.column_name,
+            **config_kwargs_,
         )
 
     with SpinnerContext(message="getting dataloader..."):
diff --git a/spd/clustering/plotting/activations.py b/spd/clustering/plotting/activations.py
index 2411eca38..dc8c8658c 100644
--- a/spd/clustering/plotting/activations.py
+++ b/spd/clustering/plotting/activations.py
@@ -2,6 +2,7 @@
 
 from collections.abc import Sequence
 from pathlib import Path
+from typing import Literal
 
 import matplotlib as mpl
 import matplotlib.pyplot as plt
@@ -20,7 +21,7 @@ def plot_activations(
     processed_activations: ProcessedActivations,
     save_dir: Path,
     n_samples_max: int,
-    pdf_prefix: str = "activations",
+    figure_prefix: str = "activations",
     figsize_raw: tuple[int, int] = (12, 4),
     figsize_concat: tuple[int, int] = (12, 2),
     figsize_coact: tuple[int, int] = (8, 6),
@@ -28,6 +29,7 @@ def plot_activations(
     hist_bins: int = 100,
     do_sorted_samples: bool = False,
     wandb_run: wandb.sdk.wandb_run.Run | None = None,
+    save_fmt: Literal["pdf", "png", "svg"] = "pdf",
 ) -> None:
     """Plot activation visualizations including raw, concatenated, sorted, and coactivations.
 
@@ -37,7 +39,7 @@ def plot_activations(
         coact: Coactivation matrix
         labels: Component labels
         save_dir: The directory to save the plots to
-        pdf_prefix: Prefix for PDF filenames
+        figure_prefix: Prefix for figure filenames
         figsize_raw: Figure size for raw activations
         figsize_concat: Figure size for concatenated activations
         figsize_coact: Figure size for coactivations
@@ -77,7 +79,7 @@ def plot_activations(
         axs_act[i].set_ylabel(f"components\n{key}")
         axs_act[i].set_title(f"Raw Activations: {key} (shape: {act_raw_data.shape})")
 
-    fig1_fname = save_dir / f"{pdf_prefix}_raw.pdf"
+    fig1_fname = save_dir / f"{figure_prefix}_raw.{save_fmt}"
     _fig1.savefig(fig1_fname, bbox_inches="tight", dpi=300)
 
     # Log to WandB if available
@@ -100,7 +102,7 @@ def plot_activations(
 
     plt.colorbar(im2)
 
-    fig2_fname: Path = save_dir / f"{pdf_prefix}_concatenated.pdf"
+    fig2_fname: Path = save_dir / f"{figure_prefix}_concatenated.{save_fmt}"
     fig2.savefig(fig2_fname, bbox_inches="tight", dpi=300)
 
     # Log to WandB if available
@@ -169,7 +171,7 @@ def plot_activations(
 
         plt.colorbar(im3)
 
-        fig3_fname: Path = save_dir / f"{pdf_prefix}_concatenated_sorted.pdf"
+        fig3_fname: Path = save_dir / f"{figure_prefix}_concatenated_sorted.{save_fmt}"
         fig3.savefig(fig3_fname, bbox_inches="tight", dpi=300)
 
         # Log to WandB if available
@@ -193,7 +195,7 @@ def plot_activations(
 
     plt.colorbar(im4)
 
-    fig4_fname: Path = save_dir / f"{pdf_prefix}_coactivations.pdf"
+    fig4_fname: Path = save_dir / f"{figure_prefix}_coactivations.{save_fmt}"
     fig4.savefig(fig4_fname, bbox_inches="tight", dpi=300)
 
     # Log to WandB if available
@@ -217,7 +219,7 @@ def plot_activations(
     add_component_labeling(ax4_log, labels, axis="x")
     add_component_labeling(ax4_log, labels, axis="y")
     plt.colorbar(im4_log)
-    fig4_log_fname: Path = save_dir / f"{pdf_prefix}_coactivations_log.pdf"
+    fig4_log_fname: Path = save_dir / f"{figure_prefix}_coactivations_log.{save_fmt}"
     fig4_log.savefig(fig4_log_fname, bbox_inches="tight", dpi=300)
 
     # Log to WandB if available
@@ -312,7 +314,7 @@ def plot_activations(
 
     plt.tight_layout()
 
-    fig5_fname: Path = save_dir / f"{pdf_prefix}_histograms.pdf"
+    fig5_fname: Path = save_dir / f"{figure_prefix}_histograms.{save_fmt}"
     fig5.savefig(fig5_fname, bbox_inches="tight", dpi=300)
 
     # Log to WandB if available
diff --git a/spd/clustering/plotting/merge.py b/spd/clustering/plotting/merge.py
index e470b3114..8a2cc20df 100644
--- a/spd/clustering/plotting/merge.py
+++ b/spd/clustering/plotting/merge.py
@@ -17,7 +17,7 @@
     figsize=(16, 10),
     tick_spacing=5,
     save_pdf=False,
-    pdf_prefix="merge_iteration",
+    figure_prefix="merge_iteration",
 )
 
 
@@ -168,7 +168,9 @@ def plot_merge_iteration(
 
     if plot_config_["save_pdf"]:
         fig.savefig(
-            f"{plot_config_['pdf_prefix']}_iter_{iteration:03d}.pdf", bbox_inches="tight", dpi=300
+            f"{plot_config_['figure_prefix']}_iter_{iteration:03d}.pdf",
+            bbox_inches="tight",
+            dpi=300,
         )
 
     if show:
diff --git a/spd/clustering/scripts/main.py b/spd/clustering/scripts/main.py
index 56cee4d84..2104482e5 100644
--- a/spd/clustering/scripts/main.py
+++ b/spd/clustering/scripts/main.py
@@ -43,6 +43,11 @@ def cli() -> None:
         default=1,
         help="Maximum number of concurrent clustering processes per device (default: 1)",
     )
+    parser.add_argument(
+        "--dataset-streaming",
+        action="store_true",
+        help="Whether to use streaming dataset loading (if supported by the dataset). see https://github.com/goodfire-ai/spd/pull/199",
+    )
     args: argparse.Namespace = parser.parse_args()
 
     logger.info("Starting clustering pipeline")
@@ -66,6 +71,7 @@ def cli() -> None:
     config.base_path = args.base_path
     config.devices = devices
     config.workers_per_device = args.workers_per_device
+    config.dataset_streaming = args.dataset_streaming
 
     logger.info(f"Configuration loaded: {config.config_identifier}")
     logger.info(f"Base path: {config.base_path}")
diff --git a/tests/clustering/scripts/cluster_ss.py b/tests/clustering/scripts/cluster_ss.py
index 6ede368f0..00ef733d6 100644
--- a/tests/clustering/scripts/cluster_ss.py
+++ b/tests/clustering/scripts/cluster_ss.py
@@ -1,7 +1,11 @@
 # %%
+import os
+
+# Suppress tokenizer parallelism warning when forking
+os.environ["TOKENIZERS_PARALLELISM"] = "false"
+
 from pathlib import Path
 
-import matplotlib.pyplot as plt
 import torch
 from jaxtyping import Int
 from muutils.dbg import dbg_auto
@@ -49,7 +53,11 @@
     n_batches=1,
     batch_size=2,
 )
-BATCHES, _ = split_dataset(config=CONFIG)
+
+BATCHES, _ = split_dataset(
+    config=CONFIG,
+    config_kwargs=dict(streaming=True),  # see https://github.com/goodfire-ai/spd/pull/199
+)
 
 # %%
 # Load data batch
@@ -85,6 +93,7 @@
     save_dir=TEMP_DIR,
     n_samples_max=256,
     wandb_run=None,
+    save_fmt="svg",
 )
 
 # %%
@@ -126,4 +135,9 @@
     distances=DISTANCES,
     mode="points",
 )
-plt.legend()
+
+# %%
+# Exit cleanly to avoid CUDA thread GIL issues during interpreter shutdown
+# see https://github.com/goodfire-ai/spd/issues/201#issue-3503138939
+# ============================================================
+os._exit(0)
diff --git a/tests/clustering/test_clustering_experiments.py b/tests/clustering/test_clustering_experiments.py
index 5031adfce..19ff937f6 100644
--- a/tests/clustering/test_clustering_experiments.py
+++ b/tests/clustering/test_clustering_experiments.py
@@ -87,6 +87,7 @@ def test_clustering_with_simplestories_config():
             "spd-cluster",
             "--config",
             str(config_path),
+            "--dataset-streaming",  # see https://github.com/goodfire-ai/spd/pull/199
         ],
         capture_output=True,
         text=True,