yw_div conda environment — H100 / CUDA 12.6 setup guide
This guide reproduces the conda environment yw_div on a target server.
- Source machine: Linux x86_64, NVIDIA RTX A6000, CUDA 12.6, Python 3.11.12
- Target machine: Linux x86_64, NVIDIA H100, CUDA 12.6 (driver ≥ 555/560)
- Core stack: Python 3.11.12, PyTorch 2.7.0+cu126, torchvision 0.22.0+cu126, torchaudio 2.7.0+cu126, Triton 3.3.0, NumPy 2.2.5
The PyTorch wheels for cu126 ship their own CUDA 12.6 runtime, cuDNN 9.5, NCCL 2.26, etc. — you do not need a system-wide CUDA toolkit, only an NVIDIA driver that supports CUDA 12.6.
0. Prerequisites on the target server
# Verify the driver supports CUDA 12.6 (driver >= 555). H100 should show CC 9.0.
nvidia-smi
# Expect: "CUDA Version: 12.6" (or higher) in the top-right of the table.
# Conda (Miniconda/Anaconda/Mambaforge) must be installed.
conda --version # any modern conda (>= 23.x) is fine
If conda is not installed:
wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh -O /tmp/miniconda.sh
bash /tmp/miniconda.sh -b -p "$HOME/miniconda3"
source "$HOME/miniconda3/etc/profile.d/conda.sh"
conda init bash # then restart your shell
1. Files in this bundle
| File | Purpose |
|---|---|
SETUP_GUIDE.md |
This guide. |
setup_yw_div.sh |
One-shot install script (recommended). |
requirements_torch.txt |
Pinned PyTorch wheels (must use the cu126 index). |
requirements_pip.txt |
All other Python packages (PyPI). |
environment_full.yml |
Full conda export from the source machine (reference only). |
environment_from_history.yml |
Minimal conda spec (reference only). |
requirements_full.txt |
Raw pip freeze from the source machine (reference only). |
Copy the entire yw_div_env/ directory to the target server (e.g. via scp -r).
2. Quick install (recommended)
cd /path/to/yw_div_env
bash setup_yw_div.sh
The script performs:
conda create -n yw_div python=3.11.12 pip(channel:conda-forge)- Pin baseline
pip / setuptools / wheel - Install PyTorch stack from
https://download.pytorch.org/whl/cu126 - Install the rest of the packages from
requirements_pip.txt - Print a sanity check (torch version, CUDA visible, device names)
To use a different env name: ENV_NAME=my_env bash setup_yw_div.sh.
Activate after install:
conda activate yw_div
3. Manual install (step by step)
If you'd rather run the steps yourself:
# 1. Create the env
conda create -y -n yw_div -c conda-forge python=3.11.12 pip
conda activate yw_div
# 2. Pin pip toolchain
pip install --upgrade pip==25.0.1 setuptools==75.8.2 wheel==0.45.1
# 3. PyTorch + torchvision + torchaudio (CUDA 12.6 wheels)
pip install --index-url https://download.pytorch.org/whl/cu126 \
torch==2.7.0+cu126 \
torchvision==0.22.0+cu126 \
torchaudio==2.7.0+cu126
# 4. Everything else
pip install -r requirements_pip.txt
4. Verification
conda activate yw_div
python - <<'PY'
import torch, torchvision, torchaudio, triton, numpy
print("torch :", torch.__version__)
print("torchvision :", torchvision.__version__)
print("torchaudio :", torchaudio.__version__)
print("triton :", triton.__version__)
print("numpy :", numpy.__version__)
print("cuda build :", torch.version.cuda)
print("cudnn :", torch.backends.cudnn.version())
print("nccl :", torch.cuda.nccl.version())
print("cuda avail :", torch.cuda.is_available())
for i in range(torch.cuda.device_count()):
name = torch.cuda.get_device_name(i)
cc = torch.cuda.get_device_capability(i)
print(f" gpu[{i}] {name} cc={cc}")
# Tiny H100 sanity op
x = torch.randn(4096, 4096, device="cuda", dtype=torch.bfloat16)
y = x @ x
torch.cuda.synchronize()
print("matmul ok :", y.shape, y.dtype, y.device)
PY
Expected on an H100 node:
cuda build : 12.6cuda avail : Truegpu[0] NVIDIA H100 ... cc=(9, 0)
5. Notes & troubleshooting
+cu126is required. Do notpip install torchwithout the index URL — that pulls a CPU build and silently breaks GPU code.- Driver too old. If
nvidia-smireportsCUDA Version: 12.5or lower, ask the admin to upgrade the driver to one that supports 12.6 (≥ 555.x). The toolkit on disk doesn't matter; the driver does. - H100 + bf16 / FP8.
torch==2.7.0+cu126already supportstorch.bfloat16and the H100 transformer engine paths via cuDNN 9.5. No extra steps required. - flash-attn / xformers. Not in this snapshot. If your project needs them, install separately, e.g.
pip install flash-attn --no-build-isolation(requiresnvcc/CUDA dev toolkit) or use a prebuilt wheel matching torch 2.7 + cu126. - Conda channel pollution. The base env on the source machine includes some conda-only packages (
conda-build,libmambapy,lief, …) that are not installed inyw_div. They are conda-runtime utilities, not project dependencies. - Re-running the script is safe to re-attempt installs but will fail at step 1 if the env already exists. Either remove it (
conda env remove -n yw_div) or pass a differentENV_NAME=. - HF cache / wandb.
huggingface_hub,wandb,tensorboardare pre-installed; configure tokens (huggingface-cli login,wandb login) before first run.
6. Removing the env
conda env remove -n yw_div