diff --git a/benchmarks/recursiongfn/Makefile b/benchmarks/recursiongfn/Makefile
new file mode 100644
index 000000000..892657d09
--- /dev/null
+++ b/benchmarks/recursiongfn/Makefile
@@ -0,0 +1,31 @@
+# Use global base if possible
+ifndef MILABENCH_BASE
+	MILABENCH_BASE="base"
+endif
+
+export MILABENCH_BASE
+
+BENCH_NAME=recursiongfn
+MILABENCH_CONFIG=dev.yaml
+MILABENCH_ARGS=--config $(MILABENCH_CONFIG) --base $(MILABENCH_BASE)
+
+all:
+	install prepare single gpus nodes
+
+install:
+	milabench install $(MILABENCH_ARGS) --force
+
+prepare:
+	milabench prepare $(MILABENCH_ARGS)
+
+tests: # install prepare
+	milabench run $(MILABENCH_ARGS)
+
+single:
+	milabench run $(MILABENCH_ARGS) --select $(BENCH_NAME)-single
+
+gpus:
+	milabench run $(MILABENCH_ARGS) --select $(BENCH_NAME)-gpus
+
+nodes:
+	milabench run $(MILABENCH_ARGS) --select $(BENCH_NAME)-nodes
diff --git a/benchmarks/recursiongfn/README.md b/benchmarks/recursiongfn/README.md
new file mode 100644
index 000000000..b8db87236
--- /dev/null
+++ b/benchmarks/recursiongfn/README.md
@@ -0,0 +1,4 @@
+
+# Recursiongfn
+
+Rewrite this README to explain what the benchmark is!
diff --git a/benchmarks/recursiongfn/benchfile.py b/benchmarks/recursiongfn/benchfile.py
new file mode 100644
index 000000000..ff486dec7
--- /dev/null
+++ b/benchmarks/recursiongfn/benchfile.py
@@ -0,0 +1,31 @@
+from milabench.pack import Package
+
+
+class Recursiongfn(Package):
+    # Requirements file installed by install(). It can be empty or absent.
+    base_requirements = "requirements.in"
+
+    # The preparation script called by prepare(). It must be executable,
+    # but it can be any type of script. It can be empty or absent.
+    prepare_script = "prepare.py"
+
+    # The main script called by run(). It must be a Python file. It has to
+    # be present.
+    main_script = "main.py"
+
+    # You can remove the functions below if you don't need to modify them.
+
+    def make_env(self):
+        # Return a dict of environment variables for prepare_script and
+        # main_script.
+        return super().make_env()
+
+    async def install(self):
+        await super().install()  # super() call installs the requirements
+
+    async def prepare(self):
+        await super().prepare()  # super() call executes prepare_script
+
+
+
+__pack__ = Recursiongfn
diff --git a/benchmarks/recursiongfn/dev.yaml b/benchmarks/recursiongfn/dev.yaml
new file mode 100644
index 000000000..8730968ff
--- /dev/null
+++ b/benchmarks/recursiongfn/dev.yaml
@@ -0,0 +1,15 @@
+
+recursiongfn:
+  inherits: _defaults
+  definition: .
+  install-variant: unpinned
+  install_group: torch
+  plan:
+    method: per_gpu
+
+  argv:
+    --batch_size: 128
+    --num_workers: 8
+    --num_steps: 100
+    --layer_width: 128
+    --num_layers: 4
diff --git a/benchmarks/recursiongfn/main.py b/benchmarks/recursiongfn/main.py
new file mode 100644
index 000000000..2933647e9
--- /dev/null
+++ b/benchmarks/recursiongfn/main.py
@@ -0,0 +1,169 @@
+# This is the script run by milabench run (by default)
+# It is possible to use a script from a GitHub repo if it is cloned using
+# clone_subtree in the benchfile.py, in which case this file can simply
+# be deleted.
+
+import datetime
+import os
+import random
+import time
+from pathlib import Path
+from typing import Callable
+
+import numpy as np
+import torch
+import torch.nn as nn
+import torchcompat.core as accelerator
+from gflownet.config import Config, init_empty
+from gflownet.models import bengio2021flow
+from gflownet.tasks.seh_frag import SEHFragTrainer, SEHTask
+from gflownet.utils.conditioning import TemperatureConditional
+from gflownet.utils.misc import get_worker_device
+from torch import Tensor
+from torch.utils.data import DataLoader, Dataset
+
+from benchmate.observer import BenchObserver
+
+
+class SEHFragTrainerMonkeyPatch(SEHFragTrainer):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self.batch_size_in_nodes = []
+
+        def batch_size(x):
+            """Measures the batch size as the sum of all nodes in the batch."""
+            return self.batch_size_in_nodes.pop()
+
+        self.observer = BenchObserver(
+            accelerator.Event,
+            earlystop=65,
+            batch_size_fn=batch_size,
+            raise_stop_program=False,
+            stdout=False,
+        )
+
+    def _maybe_resolve_shared_buffer(self, *args, **kwargs):
+        batch = super()._maybe_resolve_shared_buffer(*args, **kwargs)
+
+        # Accumulate the size of all graphs in the batch measured in nodes.
+        acc = 0
+        n = len(batch)
+        for i in range(n):
+            elem = batch[i]
+            acc += elem.x.shape[0]
+
+        self.batch_size_in_nodes.append(acc)
+        return batch
+
+    def step(self, loss: Tensor):
+        original_output = super().step(loss)
+        self.observer.record_loss(loss)
+        return original_output
+
+    def build_training_data_loader(self) -> DataLoader:
+        original_output = super().build_training_data_loader()
+        return self.observer.loader(original_output)
+
+    def setup_task(self):
+        self.task = SEHTaskMonkeyPatch(
+            dataset=self.training_data,
+            cfg=self.cfg,
+            rng=self.rng,
+            wrap_model=self._wrap_for_mp,
+        )
+
+
+class SEHTaskMonkeyPatch(SEHTask):
+    """Allows us to specify the location of the original model download."""
+
+    def __init__(
+        self,
+        dataset: Dataset,
+        cfg: Config,
+        rng: np.random.Generator = None,
+        wrap_model: Callable[[nn.Module], nn.Module] = None,
+    ):
+        self._wrap_model = wrap_model
+        self.rng = rng
+        self.models = self._load_task_models()
+        self.dataset = dataset
+        self.temperature_conditional = TemperatureConditional(cfg, rng)
+        self.num_cond_dim = self.temperature_conditional.encoding_size()
+
+    def _load_task_models(self):
+        xdg_cache = os.environ["XDG_CACHE_HOME"]
+        model = bengio2021flow.load_original_model(
+            cache=True,
+            location=Path(os.path.join(xdg_cache, "bengio2021flow_proxy.pkl.gz")),
+        )
+        model.to(get_worker_device())
+        model = self._wrap_model(model)
+        return {"seh": model}
+
+
+def main(
+    batch_size: int, num_workers: int, num_steps: int, layer_width: int, num_layers: int
+):
+    # This script runs on an A100 with 8 cpus and 32Gb memory, but the A100 is probably
+    # overkill here. VRAM peaks at 6Gb and GPU usage peaks at 25%.
+
+    config = init_empty(Config())
+    config.print_every = 1
+    config.log_dir = f"./logs/debug_run_seh_frag_{datetime.datetime.now().strftime('%Y-%m-%d_%H-%M-%S')}"
+    config.device = accelerator.fetch_device(0)  # This is your CUDA device.
+    config.overwrite_existing_exp = True
+
+    config.num_training_steps = num_steps  # Change this to train for longer.
+    config.checkpoint_every = 5  # 500
+    config.validate_every = 0
+    config.num_final_gen_steps = 0
+    config.opt.lr_decay = 20_000
+    config.opt.clip_grad_type = "total_norm"
+    config.algo.sampling_tau = 0.9
+    config.cond.temperature.sample_dist = "constant"
+    config.cond.temperature.dist_params = [64.0]
+    config.replay.use = False
+
+    # Things it may be fun to play with.
+    config.num_workers = num_workers
+    config.model.num_emb = layer_width
+    config.model.num_layers = num_layers
+    batch_size = batch_size
+
+    if config.replay.use:
+        config.algo.num_from_policy = 0
+        config.replay.num_new_samples = batch_size
+        config.replay.num_from_replay = batch_size
+    else:
+        config.algo.num_from_policy = batch_size
+
+    # This may need to be adjusted if the batch_size is made bigger
+    config.mp_buffer_size = 32 * 1024**2  # 32Mb
+    trial = SEHFragTrainerMonkeyPatch(config, print_config=False)
+    trial.run()
+    trial.terminate()
+
+
+if __name__ == "__main__":
+    import argparse
+
+    parser = argparse.ArgumentParser(description="Description of your program")
+    parser.add_argument("-b", "--batch_size", help="Batch Size", default=128)
+    parser.add_argument("-n", "--num_workers", help="Number of Workers", default=8)
+    parser.add_argument(
+        "-s", "--num_steps", help="Number of Training Steps", default=100
+    )
+    parser.add_argument(
+        "-w", "--layer_width", help="Width of each policy hidden layer", default=128
+    )
+    parser.add_argument("-l", "--num_layers", help="Number of hidden layers", default=4)
+    args = parser.parse_args()
+
+    main(
+        args.batch_size,
+        args.num_workers,
+        args.num_steps,
+        args.layer_width,
+        args.num_layers,
+    )
diff --git a/benchmarks/recursiongfn/prepare.py b/benchmarks/recursiongfn/prepare.py
new file mode 100755
index 000000000..3c9539548
--- /dev/null
+++ b/benchmarks/recursiongfn/prepare.py
@@ -0,0 +1,23 @@
+#!/usr/bin/env python
+
+import os
+from gflownet.models.bengio2021flow import load_original_model
+from pathlib import Path
+
+
+if __name__ == "__main__":
+    # If you need the whole configuration:
+    # config = json.loads(os.environ["MILABENCH_CONFIG"])
+    print("+ Full environment:\n{}\n***".format(os.environ))
+
+    #milabench_cfg = os.environ["MILABENCH_CONFIG"]
+    #print(milabench_cfg)
+
+    xdg_cache = os.environ["XDG_CACHE_HOME"]
+
+    print("+ Loading proxy model weights to MILABENCH_DIR_DATA={}".format(xdg_cache))
+    _ = load_original_model(
+        cache=True,
+        location=Path(os.path.join(xdg_cache, "bengio2021flow_proxy.pkl.gz")),
+        )
+
diff --git a/benchmarks/recursiongfn/requirements.in b/benchmarks/recursiongfn/requirements.in
new file mode 100644
index 000000000..15b6e7a55
--- /dev/null
+++ b/benchmarks/recursiongfn/requirements.in
@@ -0,0 +1,5 @@
+voir>=0.2.17,<0.3
+torch
+gflownet @ git+https://github.com/recursionpharma/gflownet@bengioe-mila-demo
+--find-links https://data.pyg.org/whl/torch-2.1.2+cu121.html
+
diff --git a/benchmarks/recursiongfn/voirfile.py b/benchmarks/recursiongfn/voirfile.py
new file mode 100644
index 000000000..d93f886cd
--- /dev/null
+++ b/benchmarks/recursiongfn/voirfile.py
@@ -0,0 +1,38 @@
+from dataclasses import dataclass
+
+from voir import configurable
+from voir.instruments import dash, early_stop, log, rate
+from benchmate.monitor import monitor_monogpu
+
+@dataclass
+class Config:
+    """voir configuration"""
+
+    # Whether to display the dash or not
+    dash: bool = False
+
+    # How often to log the rates
+    interval: str = "1s"
+
+    # Number of rates to skip before logging
+    skip: int = 5
+
+    # Number of rates to log before stopping
+    stop: int = 20
+
+    # Number of seconds between each gpu poll
+    gpu_poll: int = 3
+
+
+@configurable
+def instrument_main(ov, options: Config):
+    yield ov.phases.init
+
+    if options.dash:
+        ov.require(dash)
+
+    ov.require(
+        log("value", "progress", "rate", "units", "loss", "gpudata", context="task"),
+        early_stop(n=options.stop, key="rate", task="train"),
+        monitor_monogpu(poll_interval=options.gpu_poll),
+    )
diff --git a/benchmate/benchmate/observer.py b/benchmate/benchmate/observer.py
index 9676e8261..0a40ae11e 100644
--- a/benchmate/benchmate/observer.py
+++ b/benchmate/benchmate/observer.py
@@ -75,10 +75,13 @@ def iterate(self, iterator, custom_step=False):
     def step(self):
         self.instance.step()
     
+    def original_dataloader(self):
+        return self.instance
+    
     def loader(self, loader, custom_step=False):
         """Wrap a dataloader or an iterable which enable accurate measuring of time spent in the loop's body"""
-        if self.instance:
-            return self.instance
+        if self.instance is not None:
+            return self.instance.loader
         
         cls = TimedIterator
         if custom_step: