Versioned files

Your checkpoint and journal files are used to reconstruct the Helix Core Server database files only. Your versioned files might be stored in directories under the Helix Core Server root, and must be backed up separately.

Versioned file formats

Versioned files are stored in subdirectories beneath your server root. Text files are stored in RCS format, with filenames of the form filename,v. There is generally one RCS-format (,v) file per text file. Binary files are stored in full in their own directories named filename,d. Depending on the Helix Core Server file type selected by the user storing the file, there can be one or more archived binary files in each filename,d directory. If more than one file resides in a filename,d directory, each file in the directory refers to a different revision of the binary file, and is named 1.n, where n is the revision number.

Helix Core Server also supports the AppleSingle file format for Macintosh. These files are stored in full and compressed, just like other binary files. They are stored in the Mac’s AppleSingle file format. If need be, the files can be copied directly from the server root, uncompressed, and used as-is on a Macintosh.

Because Helix Core Server uses compression in the depot file tree, do not assume compressibility of the data when sizing backup media. Both text and binary files are either compressed by p4d (and are denoted by the .gz suffix) before storage, or they are stored uncompressed. At most installations, if any binary files in the depot subdirectories are being stored uncompressed, they were probably incompressible to begin with. (For example, many image, music, and video file formats are incompressible.)

Backing up after checkpointing

In order to ensure that the versioned files reflect all the information in the database after a post-crash restoration, the db.* files must be restored from a checkpoint that is at least as old as (or older than) your versioned files. For this reason, create the checkpoint before backing up the versioned files in the depot directory or directories.

Although your versioned files can be newer than the data stored in your checkpoint, it is best to keep this difference to a minimum. In general, you’ll want your backup script to back up your versioned files immediately after successfully completing a checkpoint.