I came across a SSD which have a very significant performance drop (about 20 times). As there is an ExFAT filesystem used, I suspect it might be due to fragmentation.
Is there a tool available in the open source / free software world (= permissive or affordable license) to de-fragment the filesystem?
Yes, I know about the Good old way of backing up, reformatting and putting back. In this case it might be quite lengthy (some TBs of data in an embedded measurement system).
gnome-disks
) tell you that random access is the problem, or is linear access also slower than you'd like?