[Facts] ZFS RAID-Z2 scrubbing speed

posted in: computer | 0
  8-core CPU Intel Xeon E5-2665
64 GB DDR3 ECC RAM
OS FreeBSD 11.2
12x hdd's RAID-Z2 (5400 rpm, SATA-2, consumer-grade)
2x ssd's L2ARC (SATA-2, consumer-grade)
1x ssd SLOG (SATA-2, consumer-grade)
pool specs: 81% full, 40% fragmentation
scrub CPU-load: 60..75 % on all cores
scrub speed after 10 minutes: max. 552 MB/s (pending 530..550 MB)