ctr-legacy-pi05-pytorch-base-and-e117-adapter-backup-20260918

Historical PI0.5 PyTorch base and grouped PEFT adapter backup

Byte-preserving archival backup of the historical E117 step-2500 format conversion, retained before source-instance storage cleanup. This historical label is distinct from later experiments reusing E117.

The original base directory is under params/base/; the matching converted grouped PEFT adapter is under params/adapter/. This is a custom backup layout, not an Orbax checkpoint or a standalone Hugging Face pipeline. Original JSON configuration and conversion receipts are preserved. The source converter used PEFT 0.17.1 and a compatible OpenPI PI0Pytorch implementation; retain its original loader and normalization. The original converted directories did not contain normalization statistics; this backup does not invent or replace them.

A fresh CPU process decoded every safetensors tensor, verified finite values, and matched both file hashes to the original conversion receipt. No full policy reconstruction, simulation evaluation, optimizer update, or new scientific qualification was performed. No optimizer or resumable training state is included.