Manual:$wgHashedUploadDirectory

Files and file uploads: $wgHashedUploadDirectory
If true, uses the /a/ab/foo.jpg directory structure.
Introduced in version:	1.4.0 (r5578)
Removed in version:	Still in use
Allowed values:	(boolean)
Default value:	true
Other settings: Alphabetical | By function

Details

If true, uploaded files will be distributed into sub-directories of $wgUploadDirectory based on the first two characters of the md5 hash of the filename. (e.g. $IP /images/a/ab/foo.jpg) Creation of such subdirectories is handled automatically. This is used to avoid having too many files in one folder because some filesystems don't perform well with large numbers of files in one folder.

The algorithm for that is based on a md5 of the name, the first hex character is used for the first directory, then the first two characters are used for the subdirectory.

Foo.png → md5 of filename = f865cbca12286c1c5b7616b4a70fbf68 → f + f8 = $IP /images/f/f8/Foo.png

If false, all images are uploaded in $wgUploadDirectory itself. (e.g. $IP /images/foo.jpg)

This parameter should not be changed after the first image or file has been uploaded (or else you will need to move all previous uploaded pictures). It will result in PHP errors (see the discussion page) if articles with the old logic try to find their pictures, since the image path is calculated and not stored in the database.

If you set $wgLocalFileRepo , this variable will be ignored.

See also

• $wgHashedSharedUploadDirectory — for shared uploads.
• $wgLocalFileRepo — for changing the hash level (number of characters used from the hash).