[batch2] back off in scheduler loop (#7637)
[batch2] back off in scheduler loop (#7637)

* back off in scheduler loop

* fix

* fix

* fix

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