I’ve had this issue since the first day I started using linux about 15 years ago. Always the same issue, transfers start fine and slows down to a crawl, only on USB sticks.
The USB sticks are fine, I can make bootable sticks in five minutes but if I copy a file of similar size to them is half an hour and then five to ten more minutes waiting to be able to safely remove the drive.
There are dozens of forum posts, some blaming the drives, others the GUI, dirty buffers, outdated kernels, fastboot for some reason. Others marked as solved without a solution because it magically solved itself.
Right now I’m not at home so I can’t check, I drag and drop the files with the default file browser on cinnamon.
This time I formatted the stick in ext4 but it was the same with NTFS.
in your shoes, i would switch to a terminal to get hard numbers instead of gut feelings and try different file systems and copy utilities.
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