Mac hard disk purgeable how to#

The process can continue to use that file, so it still needs space, but no other process can get to it since it no longer has an entry on the filesystem-its space will get reclaimed when the file is closed (such as when the process that has it open finally terminates).ДЄnd that was just in the traditional filesystem world. Those two numbers arenвЂ™t guaranteed to match up, because a process can create a file, open a file, remove it, but still leave it open. This is the number you see at the top of the window of the file browser, and is much like what youвЂ™d see if you ran du on that same folder at the command line. The other number is what you see when you start at the top directory on the disk and work your way through each file on the disk, adding up the sizes as you go. This reports the same numbers youвЂ™d see if you ran df at the command line. The drive list (the first window you see when you open the app) asks each drive for its current usage stats and simply reports those. OmniDiskSweeper has two ways of finding the amount of space being used on a disk. But even though it shows up in the summary, it wonвЂ™t show up when you browse the disk looking for files to delete-so OmniDiskSweeper will end up reporting different numbers for space used based on how it scans your disk. But itвЂ™s not truly cleared up from the disk yet and still shows up in OmniDiskSweeperвЂ™s summary list.

Mac hard disk purgeable how to#

The вЂњpurgeableвЂќ space is space that the operating system knows how to reclaim when you try to create files that need that space. When you open Disk Utility and select your disk, you can see more detail about how Apple treats available disk space: вЂњAbout This MacвЂќ includes вЂњpurgeableвЂќ space as free/available space. If you check the amount of free space listed in About This Mac and the amount of free space listed for the same drive in OmniDiskSweeper, youвЂ™ll see different numbers.