In this article on Quora 'Does disk fragmentation occur in Linux? If not, why?' it explains that Linux (EXT4) does not fragment any disk. Windows however will (FAT 32/NTFS).

Fragmentation only happens on HDDs (the ones with platters and readheads in them).So you can defrag them once in a while for better performance.

Fragmentation does not happen on SSDs. Don't perform a defragmentation on these kind of disks. It is useless and the read/writes shorten its lifespan.

So it really depends on what kind of disk(s) you have in your system and what filesystem you use.