I've been trying to create a backup for a very large MyISAM DB with mysqldump and I've noticed that some of the tables have variations in index sizes after restoring.
For example, one of my larger tables has an index length of 50316242944 and the restored dump of that table has an index length of 50227628032
I've run optimize table and have done a checksum and everything seems to be fine. I've even run ALTER TABLE generic_dummy_table_name ORDER BY datetime; which I found on a similar question on this site.
Could someone explain to me why there is such a large difference in index length between my tables and if there is an easy way to fix it?