Version Control with Subversion

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Chapter 5: Repository Administration

from disk to conserve space. Use the svnadmin list-unused-dblogs command to list

the unused logfiles:

$ svnadmin list-unused-dblogs /path/to/repos

/path/to/repos/log.0000000031

/path/to/repos/log.0000000032

/path/to/repos/log.0000000033

$ svnadmin list-unused-dblogs /path/to/repos | xargs rm

## disk space reclaimed!

To keep the size of the repository as small as possible, Subversion uses deltification

(or, deltified storage) within the repository itself. Deltification involves encoding the

representation of a chunk of data as a collection of differences against some other

chunk of data. If the two pieces of data are very similar, this deltification results in

storage savings for the deltified chunk—rather than taking up space equal to the size

of the original data, it only takes up enough space to say, “I look just like this other

piece of data over here, except for the following couple of changes.” Specifically,

each time a new version of a file is committed to the repository, Subversion encodes

the previous version (actually, several previous versions) as a delta against the new

version. The result is that most of the repository data that tends to be sizable—

namely, the contents of versioned files—is stored at a much smaller size than the

original ...