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. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1880943 Title: [focal] disk I/O performance regression To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1880943/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs