Disk usage (Alt+W)

Where the space goes. Alt+W logs the whole branch of the current directory and lists its folders and files by the space they take, largest first, with a bar and their share of the directory. Enter goes into a folder; folder by folder, you get down to what fills the disk.

       32.9 GiB ████████████████   45%   wsl-ubuntu-backup.tar
       18.9 GiB █████████▏         26%  /projetos
 .      5.5 GiB ██▋               7.6%  /.local
 >    154.6 MiB                      -  /boot

• The bar is drawn against the largest item of the directory, so the differences between the items show, on a track as wide as the largest; the percentage is the item’s share of the directory. The color says how much that share is: up to 10% (green, in most themes), up to 40% (amber), more (red). Each theme has its own (bar_low, bar_mid and bar_high in [colors]).
• Folders and files are mixed, by size: a single large file (an old backup, an ISO image) shows among the folders. Folders start with /.
• The line at the bottom has the totals of the directory: on the disk, apparent, the number of files, and how much they are of the disk’s used space and of the whole disk. At the top of a disk, it says how much of the used space was found: what is missing is in folders that could not be read, in the file system’s own data, or in deleted files still open.
• The panel on the right shows the item under the cursor: the space on the disk and apparent, files, date, and its share of the used space and of the disk.

On the disk or apparent

By default, sizes are the space on the disk, as du counts it: a file takes whole blocks (4 KiB, usually), so a small file takes more than its size, and a sparse file (a virtual machine’s disk) or a compressed one less. A switches to the apparent size, the files’ own sizes. The line at the bottom always shows both.

What the analysis counts

• One disk at a time. Another file system mounted inside the branch (another disk, /boot, a USB drive, a folder mounted by rclone, /proc) is not logged or counted: it shows with > and the space that file system uses, and Enter starts an analysis of it.
• Hard links count once. Two names for the same file take its space once: the first found counts, the others show with H and no size.
• Hidden files count, even when the tree does not show them, so that the totals add up.
• Links (@) count for the link itself; they are not followed.

Marks

Acting on what you find

The questions are the same as in the file window, and the totals follow right after, with the view still open.

• Del on a folder deletes it with all it holds, to the trash if that is your setting; Alt+P does it permanently, with the typed confirmation of Prune.
• Tagging a folder tags all its files, hidden ones too. ■ marks a file or a whole folder tagged, □ a folder partly tagged, and the line at the bottom says how many are tagged in the folder listed, and how much they take. Ctrl+D deletes those. The tags stay when you close the view, for Copy or Move.
• Another disk is never touched. A > line cannot be tagged or deleted, and tagging or deleting a branch stops where another disk is mounted. Del refuses a folder with a disk mounted inside it; Alt+P deletes all but that.
• In an archive or on a remote machine, only tagging and viewing work.

Keys

Tab, F8, Alt+X (the terminal) and F12 work as usual with the view open.

Analyzing a large disk logs every folder into memory: it takes a while (the footer shows the progress, and Esc cancels) and some memory, about a few hundred megabytes for millions of files. As an ordinary user, some folders of the system cannot be read (!), so the totals of / are short: the line at the bottom says how many.