2023 update: it's likely the disk I used was damanged, changed to a new disk and didn't have issue with ext4 in general.



====== Original note ======

Issue: on windows, observed external SSD has random 100% activity and 0 read/writes, I/O operation hangs, can lead to disconnect

Not sure which adjustment actually resolved issue:

1. Device Manager -> Disk -> properties -> policies -> Better performance (Enable write caching)
2. Device Manager -> (all usb controllers) -> properties -> power management -> uncheck "Allow the computer to turn off this device to save power"
3. Edit power plan -> Change advanced power settings -> USB settings -> USB selective suspend setting -> Disabled on all cases
4. https://www.reddit.com/r/techsupport/comments/6ciyje/disk_activity_on_ssd_spikes_to_100_and_freezes_at/
5. https://beebom.com/how-fix-100-disk-usage-windows-11/
   1. Disable SysMain (Superfetch) Service
   2. Disable Connected User Experiences and Telemetry
   3. Disable Windows Search


Steam download causing the same issue: 
1. https://www.reddit.com/r/buildapc/comments/kuhi8q/comment/jfrbcrs/?utm_source=reddit&utm_medium=web2x&context=3


Other observasions:
1. Seems disk are more likely to hit 100% usage when pluggin through dock or hub
2. If using dock or hub, plug the disk into the type-C display output port (use one that supports it).
   

 ## Disable auto mount
1. /etc/udev/rules.d/99-external-drive-mount.rules
2. Comment out script
3. sudo udevadm control --reload


## Linux, disk related
Copy data from one drive to another
https://unix.stackexchange.com/questions/450420/copying-files-from-one-disk-to-another-disk

Maybe resolve read-only on SD cards
https://www.reddit.com/r/SteamDeck/comments/v1l2am/question_steam_deck_sd_card_is_readonly_when_i/

Manual mount to resolve read-only
https://askubuntu.com/questions/333287/how-to-fix-external-hard-disk-read-only

Resolve read-only after unexpected disconnection
https://superuser.com/questions/1711832/linux-mounts-ext4-external-drive-read-only