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fileprune dds

A pruning-hook and a disk platter


Fileprune will delete files from the specified set targetting a given distribution of the files within time as well as size, number, and age constraints. Its main purpose is to keep a set of daily-created backup files in managable size, while still providing reasonable access to older versions. Specifying a size, file number, or age constraint will simply remove files starting from the oldest, until the constraint is met. The distribution specification (exponential, Gaussian (normal), or Fibonacci) provides finer control of the files to delete, allowing the retention of recent copies and the increasingly agressive pruning of the older files. The retention schedule specifies the age intervals for which files will be retained. As an example, an exponential retention schedule for 10 files with a base of 2 will be
1 2 4 8 16 32 64 128 256 512 1024

The above schedule specifies that for the interval of 65 to 128 days there should be (at least) one retained file (unless constraints and options override this setting). Retention schedules are always calculated and evaluated in integer days. By default fileprune will keep the oldest file within each day interval allowing files to migrate from one interval to the next as time goes by. It may also keep additional files, if the complete file set satisfies the specified constraint. The algorithm used for prunning does not assume that the files are uniformally distributed; fileprune will successfully prune file collections stored at irregular intervals.

You can read more in the article Organized pruning of file sets. ;login:, 28(3):39-42, June 2003.


The current fileprune version is 1.11. The following pages do not contain navigation links. Following a link will open a new browser window.


Source Code Repository

The fileprune source code repository is available on GitHub. You can clone it by running the following command.
git clone
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