I have an 512 GB SSD on my MacBook Retina with one of the volumes disks0s6 formatted with exFat to use it on both Mac and Windows.
diskutil info disk0s6:
Device Identifier: disk0s6 Device Node: /dev/disk0s6 Part of Whole: disk0 Device / Media Name: Basic data partition Volume Name: WORK Escaped with Unicode: WORK Mounted: Yes Mount Point: /Volumes/WORK Escaped with Unicode: /Volumes/WORK File System Personality: ExFAT Type (Bundle): exfat Name (User Visible): ExFAT Partition Type: Microsoft Basic Data OS Can Be Installed: No Media Type: Generic Protocol: PCI SMART Status: Verified Volume UUID: 40CF8BFC-3143-3BB9-B659-DE1A62DCA9E6 Total Size: 54.1 GB (54117007360 Bytes) (exactly 105697280 512-Byte-Units) Volume Free Space: 36.1 GB (36128292864 Bytes) (exactly 70563072 512-Byte-Units) Device Block Size: 512 Bytes Read-Only Media: No Read-Only Volume: No Ejectable: No Whole: No Internal: Yes Solid State: Yes
I have lots of small files in that volume and my small files took to much physical space so I want to reformat the volume with a minimum Device Block Size and Cluster Size so my small files won't take any additional space. How can I do that in OS X?
Here is an example of files in folder
bower_components which is
46.1 MB taking
9.75 GBspace on the disk (printed from windows):
As you can see 131072 bytes in each allocation unit - that is my current cluster size being created by Mac DiskUtil default
Just booted back to Mac and run the command
sudo newfs_exfat -N /dev/disk0s6:
Reformatting existing ExFAT volume Partition offset : 871407616 sectors (446160699392 bytes) Volume size : 105697280 sectors (54117007360 bytes) Bytes per sector : 512 Bytes per cluster: 131072 FAT offset : 2048 sectors (1048576 bytes) # FAT sectors : 3328 Number of FATs : 1 Cluster offset : 6144 sectors (3145728 bytes) # Clusters : 412856 Volume Serial # : 0227bd88 Bitmap start : 2 Bitmap file size : 51607 Upcase start : 3 Upcase file size : 5836 Root start : 4
So looks like chkdisk showed same
131072 bytes per cluster