Speaking about which, it would probably be good to adjust a little how
the filesystem is created and mounted (both in xfs and ext3/4 cases).
E.g. lazy-count=1 is still not the default last time I checked mkfs.xfs.
And even ext4.txt from kernel documentation recommends mounting it with
data=writeback,nobh when doing comparison with metadata journaling
filesystems (the same would go for ext3).
Along with different journal sizes, keeping an eye on stripe &
stripe-width, and other settings that might be of interest.
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