

Ask HN: Which disk defragmentation algorithms are used in major OS? - pedrorijo91

Which algorithms are used to make disk defragmentation on OS X, Windows, and some Linux distro?
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jerven
Its really a question of per file system as that makes a real difference.

XFS and ext4 will online defrag, i.e. when your volume is les than 90% full
you don't worry about it, if its fuller than that fragmentation is not the
problem to worry about.

BTRFS and other COW fragment easily but advantage means fragmentation is not
your prime concern. Also large single write files are not the problem. When
using NOCOW on a directory see above.

MAC OS X you will have terrible performance anyway... Relatively speaking if
you have more than 2 disks per volume.

Windows... no idea to be honest

