mac os extended journaled vs non journaled

macOS can only read an NTFS-formatted drive.

NTFS (New Technology File System), introduced by Microsoft in 1993, is the default file system of Windows PCs. exFAT is also vulnerable to file corruption and doesn't have support for metadata like HFS+. The maximum volume size and file size of exFAT is 128 PB, which is smaller than HFS+. NTFSĮxFAT (Extended File Allocation Table), developed by Microsoft in 2006, is the best cross-platform file system that can be read or written by macOS and Windows. If a system crash and the file system becomes unreadable, the journaling log can help locate files on the drive.ĭespite all of its benefits, HFS+ is criticized for the lack of standard features to other file systems such as checksums, snapshotting, and nanosecond timestamp. Better data securityĪpple added the journaling feature to HFS+ to improve data reliability in Mac OS X 10.2.2, which soon became the default in Mac OS X 10.3. HFS+ employs UTF-16 to encode files and folders and permits file names up to 255 characters, making it easier to have a descriptive name. Maximum size of a file and a volume: 8 EB Internationally friendly file names Maximum number of files in a volume: 2.1 billion This allows more allocation blocks and a smaller block size, which means less space is wasted. HFS+ uses a 32-bit value to address allocation blocks, two times larger than its predecessor HFS (stands for Hierarchical File System). Features of HFS+ Better use of Disk Space Without file systems like HFS+, saving a file to a drive is like throwing a rock into the sea, impossible to be found. It creates a directory that expands as files are added to the drive and records metadata and file names. HFS+ is a file system that is significant for making full use of a storage device and how data is retrieved and saved. Startup File: For booting of non-Mac computers What is HFS+ used for? It stores the first eight extents of each fork.Īttributes File: B-tree with information of additional fork.Įxtents Overflow File: B-tree for the rest of the extents that catalog file doesn't store. Volume Header: Store information about the volume, such as creation time and the number of files.Īllocation File (bitmap): Track if an allocation block is used or free.Ĭatalog File: B-tree that describes the folder and file structure on a volume. HFS+ uses six main interrelated structures to manage data on the volume. Now you can see the file system listed under your drive name on the pop-up window. Click View > Show All Devices, then select your drive from the left panel. On your Mac, click Launchpad > Other folder, then choose the Disk Utility app. To find out if your file system is HFS+ or APFS: You can't read or write to a Mac-formatted external hard drive on a Windows PC because your Mac drive is usually formatted with HFS+ or APFS, which is incompatible with Windows. All Mac operating systems since Mac OS 8.1 (read & write support).

Mac os extended journaled vs non journaled