use correct fsdp act ckpt & redo benchmark

[ByronHsu]

Summary

1. switch to correct fsdp
2. redo benchmark on top
3. add efficiency callback

TODO: clean up the code & fix the path

Testing Done

• run make test to ensure correctness
• run make checkstyle to ensure code style
• run make test-convergence to ensure convergence

jobuser [ ~/Liger-Kernel ]$ make checkstyle
flake8 .; flake8_status=$?; \
isort .; isort_status=$?; \
black .; black_status=$?; \
if [ $flake8_status -ne 0 ] || [ $isort_status -ne 0 ] || [ $black_status -ne 0 ]; then \
        exit 1; \
fi
Skipped 1 files
All done! ✨ 🍰 ✨
48 files left unchanged.