Plain read/write (UDRW), sparse image (UDSP), and sparse bundle (UDSB) compared for storage efficiency, performance, and convenience.
encryption
Three types of Disk Image, encrypted or not, tested when freshly made or used and remounted. So many variations, but only one type of Disk Image can be trusted for writing.
A Mac Studio Max has an SSD delivering up to 7.4 GB/s, and a CPU up to 50% faster than a 16-core Xeon. Why does it write an encrypted disk image at the speed of a slow hard disk?
How to work out how many threads and which cores are needed to achieve a compression rate up to 1.7 GB/s, and how to estimate power and energy.
Provided in Archive Utility and three command tools, its LZFSE compression even supports APFS special files like clones and sparse files.
On T2 and M1 Macs, FileVault provides robust protection of the Data volume on internal storage without any performance penalty.
Maybe you’ve just forgotten the password, or perhaps the owner/user of the Mac is no longer able to enter it. How to restore access to different models.
What is FileVault encryption? Is it the same as that on an M1 Mac’s internal SSD, or something different? How can you use it instead of overwriting an SSD? Which boot volumes are encrypted?
Securing sensitive data from access by others, and safeguarding it from loss of damage, is common. Solutions range from encrypted images to specialist external disks.
APFS adds 6 volume roles, including one which supports Time Machine backups. And per-file encryption is coming.
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