Installation

Requirements

• Python 3.10+

• A working PyTorch install (torch >= 2.6).

• A PyTorch GPU backend exposed through torch.cuda for tracing and simulation. SysSim uses PyTorch fake tensors marked with device="cuda", so PyTorch still needs GPU dispatch to build the operator graph. Any GPU backend supported through that PyTorch interface can be used. Profiling real layers for a calibrated estimator also needs GPUs.

SysSim depends on torch, megatron-core, megatron-bridge, numpy, pandas, pyarrow, pyyaml, scikit-learn, lightgbm, and transformers (installed automatically).

Install from source

git clone https://github.com/AISysSim/SysSim.git
cd SysSim
pip install -e .

Verify

syssim --help

You should see the run, memory, summary, sweep, profile, and calibrate subcommands. run is the CLI name for the full simulate mode. Continue to Quickstart.