[batch] Get rid of double copying in io (#9571)
[batch] Get rid of double copying in io (#9571)


danking/hail,cseed/hail,cseed/hail,cseed/hail,cseed/hail,danking/hail,cseed/hail,hail-is/hail,hail-is/hail,cseed/hail,hail-is/hail,danking/hail,danking/hail,danking/hail,danking/hail,danking/hail,hail-is/hail,hail-is/hail,hail-is/hail,cseed/hail,cseed/hail,hail-is/hail,hail-is/hail,danking/hail