040000 tree 51a4547d13809820740f9c4689eea253b146b88f	cpu
040000 tree 862bca4f006c8f8e9b20c5e73506cdcf8fc3c547	docker
040000 tree 30e476591f8cbe2dade6459a59539934c1c6ae86	gpu
040000 tree 2a0fd3b0c22334f5bf5bc3f9318746b7f1486640	singa