How can it take over 5 hours to back up 79 GB of files to a network share? That’s an average transfer rate of 4 MB/s, probably slower than your Internet connection.
backup
Provided it doesn’t have to back up large folders containing many small files, Time Machine backing up to APFS on a network share works well.
The first full backup is performed as a manual backup, and largely occurs in file-by-file copying from source to the backup store. It is more efficient than to HFS+, but differences could be less than 10%.
Should now be fully compatible with all locales, calendars, and with both 12- and 24-hour clocks.
A summary of the known benefits and current limitations of Time Machine backups to APFS, with links to more detailed accounts.
Sparse bundles, sparse files, and sparse matrices explained in a nutshell, and how a sparse bundle could have a band which is a sparse file containing a sparse matrix.
Does Big Sur’s Time Machine preserve sparse files and clones when backing up to APFS volumes?
It’s common to want or have to change either the source or destination disk for backups. How well does Time Machine to APFS cope with that?
How to bring a Time Machine backup to its knees: get it to back up a sparse file to an HFS+ disk. It’ll take forever and run you out of free space.
Given their very different structure, backups on APFS disks shouldn’t require routine maintenance. Checking and repair is performed using Disk Utility.
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