Filesystems: Btrfs

In the previous article , we explored XFS—a filesystem built for extreme scale that divides the disk into independent Allocation Groups, each with its own B+ trees for free space, inodes, and extent tracking. XFS, like every filesystem we’ve covered in this series, shares one fundamental characteristic with ext4, NTFS, and FAT32: it modifies data in place. When you update a block, the new data overwrites the old data at the same disk location.