Comment 10 for bug 1880943

For any future travelers this issue was caused by the much debated ext4lazyinit "feature".

# iotop

Total DISK READ: 0.00 B/s | Total DISK WRITE: 0.00 B/s
Current DISK READ: 0.00 B/s | Current DISK WRITE: 7.38 M/s
    TID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND
    947 be/4 root 0.00 B/s 0.00 B/s 0.00 % 2.96 % [ext4lazyinit]

While it on paper is accounting for a small percentage of the IO it will incur a noticeable performance hit to the system until it is done.