3 or 4 fragments in a 900mb file is very good.  Fragmentation becomes a problem when a file of that size has more like 100+ fragments.  It isn't uncommon for fat or ntfs to fragment such a file into several hundred pieces.

You generally won't see better than that at least on older ext4 filesystems because the maximum size of a block group is 128 MB, and so every 128 MB the contiguous space is broken by a few blocks for the allocation bitmaps and inode tables for the next block group.  A more recent ext4 feature called flex_bg allows packing a number of ( typically 16 ) block groups' worth of these tables together, leaving longer runs of allocatable blocks but depending on your distribution and what version of e2fsprogs was used to format it, this option may not have been used.

You can use tune2fs -l to check the features enabled when your filesystem was formatted.

Why are these files in an ext4 volume fragmented?
I have an encounter in which my party will be fighting a slime that deals damage to their armor and weapons. My whole party has at least 2 masterworked items. Does masterwork imply that the items can not be broken?

Thank You
