Correction to sync-system-status.txt : the charts dir contains around 400 items: 390 mostly small files and 10 dirs of around 5 depth. # cat /sys/block/sda/queue/scheduler mq-deadline kyber [bfq] none # cat /sys/block/sdb/queue/scheduler mq-deadline kyber [bfq] none linux --------- Linux 6.3.4-arch2-1 coreutils 9.3-1 Note: I can reproduce the issue. During copy and sync on usb key: sync took around 10 min. $ top |grep D PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.04 kworker/u4:3+flush-8:16 2008 root 20 0 0 0 0 D 0.3 0.0 0:00.01 kworker/u4:2+events_freezable_power_ 705 root 20 0 0 0 0 D 0.3 0.0 0:04.10 usb-storage 2008 root 20 0 0 0 0 D 0.3 0.0 0:00.02 kworker/u4:2+events_freezable_power_ 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.05 kworker/u4:3+flush-8:16 1735 root 20 0 0 0 0 D 0.3 0.0 0:00.68 kworker/u4:0+events_freezable_power_ 705 root 20 0 0 0 0 D 0.3 0.0 0:04.11 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.06 kworker/u4:3+flush-8:16 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.07 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.12 usb-storage 2015 root 20 0 0 0 0 D 0.3 0.0 0:00.02 kworker/u4:5+ext4-rsv-conversion 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.08 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.13 usb-storage 1965 root 20 0 0 0 0 D 0.3 0.0 0:00.35 kworker/u4:1+events_freezable_power_ 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.09 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.14 usb-storage 1965 root 20 0 0 0 0 D 0.3 0.0 0:00.38 kworker/u4:1+ext4-rsv-conversion 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.10 kworker/u4:3+flush-8:16 1934 root 20 0 0 0 0 D 0.3 0.0 0:00.33 kworker/u4:4+events_freezable_power_ 2008 root 20 0 0 0 0 D 0.3 0.0 0:00.05 kworker/u4:2+ext4-rsv-conversion 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.11 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.15 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.12 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.16 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.13 kworker/u4:3+flush-8:16 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.14 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.17 usb-storage 2008 root 20 0 0 0 0 D 0.3 0.0 0:00.11 kworker/u4:2+events_freezable_power_ 2008 root 20 0 0 0 0 D 0.3 0.0 0:00.12 kworker/u4:2+events_freezable_power_ 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.15 kworker/u4:3+flush-8:16 1996 root 20 0 0 0 0 D 0.3 0.0 0:00.02 jbd2/sdb1-8 705 root 20 0 0 0 0 D 0.3 0.0 0:04.18 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.16 kworker/u4:3+flush-8:16 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.17 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.19 usb-storage 2015 root 20 0 0 0 0 D 0.3 0.0 0:00.15 kworker/u4:5+ext4-rsv-conversion 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.18 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.20 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.19 kworker/u4:3+flush-8:16 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.20 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.21 usb-storage 2008 root 20 0 0 0 0 D 1.0 0.0 0:00.24 kworker/u4:2+ext4-rsv-conversion 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.21 kworker/u4:3+flush-8:16 1934 root 20 0 0 0 0 D 0.3 0.0 0:00.35 kworker/u4:4+events_freezable_power_ 705 root 20 0 0 0 0 D 0.3 0.0 0:04.22 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.22 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.23 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.23 kworker/u4:3+flush-8:16 2015 root 20 0 0 0 0 D 0.3 0.0 0:00.22 kworker/u4:5+events_freezable_power_ 1934 root 20 0 0 0 0 D 0.3 0.0 0:00.38 kworker/u4:4+events_freezable_power_ 2015 root 20 0 0 0 0 D 0.3 0.0 0:00.23 kworker/u4:5+ext4-rsv-conversion 1934 root 20 0 0 0 0 D 0.3 0.0 0:00.39 kworker/u4:4+events_freezable_power_ 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.24 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.24 usb-storage 1965 root 20 0 0 0 0 D 0.3 0.0 0:00.57 kworker/u4:1+events_freezable_power_ 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.25 kworker/u4:3+flush-8:16 1934 root 20 0 0 0 0 D 0.3 0.0 0:00.42 kworker/u4:4+events_freezable_power_ 705 root 20 0 0 0 0 D 0.3 0.0 0:04.25 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.26 kworker/u4:3+flush-8:16 1965 root 20 0 0 0 0 D 0.3 0.0 0:00.58 kworker/u4:1+events_freezable_power_ 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.27 kworker/u4:3+flush-8:16 1735 root 20 0 0 0 0 D 0.3 0.0 0:00.77 kworker/u4:0+events_freezable_power_ 705 root 20 0 0 0 0 D 0.3 0.0 0:04.26 usb-storage 2015 root 20 0 0 0 0 D 0.3 0.0 0:00.36 kworker/u4:5+ext4-rsv-conversion 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.28 kworker/u4:3+flush-8:16 705 root 20 0 0 0 0 D 0.3 0.0 0:04.27 usb-storage 1688 root 20 0 0 0 0 D 0.3 0.0 0:01.29 kworker/u4:3+flush-8:16 2059 root 20 0 6048 1176 1044 D 1.7 0.1 0:00.05 umount linux-lts --------- linux-lts 6.1.31-1 coreutils 9.3-1 No errors. sync took around 1 min. $ top |grep D PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 70 root 20 0 0 0 0 D 0.7 0.0 0:00.23 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.05 usb-storage 11 root 20 0 0 0 0 D 0.3 0.0 0:00.85 kworker/u4:1+phy0 70 root 20 0 0 0 0 D 0.3 0.0 0:00.25 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.06 usb-storage 70 root 20 0 0 0 0 D 0.3 0.0 0:00.26 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.07 usb-storage 70 root 20 0 0 0 0 D 0.3 0.0 0:00.27 kworker/u4:5+flush-8:16 70 root 20 0 0 0 0 D 0.3 0.0 0:00.28 kworker/u4:5+flush-8:16 70 root 20 0 0 0 0 D 0.3 0.0 0:00.29 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.08 usb-storage 11 root 20 0 0 0 0 D 0.0 0.0 0:00.88 kworker/u4:1+events_freezable_power_ 70 root 20 0 0 0 0 D 0.3 0.0 0:00.30 kworker/u4:5+flush-8:16 70 root 20 0 0 0 0 D 0.3 0.0 0:00.31 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.09 usb-storage 11 root 20 0 0 0 0 D 0.0 0.0 0:00.90 kworker/u4:1+ext4-rsv-conversion 70 root 20 0 0 0 0 D 0.7 0.0 0:00.33 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.10 usb-storage 31 root 20 0 0 0 0 D 0.7 0.0 0:00.05 kworker/u4:2+events_freezable_power_ 70 root 20 0 0 0 0 D 0.3 0.0 0:00.34 kworker/u4:5+flush-8:16 737 root 20 0 0 0 0 D 0.3 0.0 0:00.01 jbd2/sdb1-8 11 root 20 0 0 0 0 D 0.0 0.0 0:00.90 kworker/u4:1+ext4-rsv-conversion 710 root 20 0 0 0 0 D 0.3 0.0 0:00.11 usb-storage 11 root 20 0 0 0 0 D 0.0 0.0 0:00.90 kworker/u4:1+events_freezable_power_ 70 root 20 0 0 0 0 D 0.7 0.0 0:00.36 kworker/u4:5+flush-8:16 31 root 20 0 0 0 0 D 0.3 0.0 0:00.06 kworker/u4:2+events_freezable_power_ 710 root 20 0 0 0 0 D 0.3 0.0 0:00.12 usb-storage 70 root 20 0 0 0 0 D 0.3 0.0 0:00.37 kworker/u4:5+flush-8:16 70 root 20 0 0 0 0 D 0.3 0.0 0:00.38 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.13 usb-storage 70 root 20 0 0 0 0 D 0.3 0.0 0:00.39 kworker/u4:5+flush-8:16 70 root 20 0 0 0 0 D 0.3 0.0 0:00.40 kworker/u4:5+flush-8:16 710 root 20 0 0 0 0 D 0.3 0.0 0:00.14 usb-storage 70 root 20 0 0 0 0 D 1.0 0.0 0:00.43 kworker/u4:5+flush-8:16 11 root 20 0 0 0 0 D 0.3 0.0 0:00.94 kworker/u4:1+events_freezable_power_ 710 root 20 0 0 0 0 D 0.3 0.0 0:00.15 usb-storage 11 root 20 0 0 0 0 D 0.0 0.0 0:00.94 kworker/u4:1+events_freezable_power_ 710 root 20 0 0 0 0 D 0.3 0.0 0:00.16 usb-storage 9 root 20 0 0 0 0 D 0.0 0.0 0:00.35 kworker/u4:0+events_freezable_power_ 85 root 0 -20 0 0 0 D 0.3 0.0 0:00.09 kworker/u5:0+i915_flip 85 root 0 -20 0 0 0 D 0.3 0.0 0:00.12 kworker/u5:0+i915_flip Note the difference in TIME column in 'top |grep D' for linux and linux-lts.