Sorry for too many questions today. 

today I was doing restart trying to save time, however numerical performance after restart was so poor. so I have to kill it and ran from the beginning again. In restart inp, I just input *restart, read after first line of heading. in command windows, I submit restart job using abq2020 job=new oldjob=old int cpus=4. 

Here are the screenshot for both restart(left) and no restart case(right). You can see from first figure(restart case, from step 28 to 37, it took more iterations for each step and there are severe discontinuity on step 37). The 2nd figure is no restart case ( exact same inp file), where numerical performance is much better. Just wondering why? Thank you so much!