centos – How long should RAID 10 syncing stay at ‘recovery = 99.9%’?

After replacing a failty disk in a (CentOS 7) RAID 10, the syncing is at the following stage for quite some time now:

md10 : active raid10 sdp1(9) sdo1(8)(S) sdw(6) sdq(5) sdn(4) sdm(3) sdl(2) sdk(1) sdj(0)
      11720536064 blocks super 1.2 512K chunks 2 near-copies (8/7) (UUUUUUU_)
      (===================>.)  recovery = 99.9% (2930134016/2930134016) finish=0.0min speed=0K/sec
      bitmap: 88/88 pages (352KB), 65536KB chunk

Is that normal (I should be patient), or does it indicate a problem?