How good is Subversion at storing lots of binary files? [closed]
I'm looking for a place to put a few GB of documents (mostly .doc and .xls). My team already has a Subversion server set up for managing the documents we create, so I'd prefer to use that if possible. How well will Subversion handle all this extra stuff? Most of it is legacy information and will only ever have one version, but it is possible that a few documents could be updated.
I've been warned that SVN isn't particularly lots-of-big-binary-files-friendly. I'm wary of trying it to see whether it works since they'll always be in the repository history even if I later delete them.
Any alternatives? We'll need the ability to comment on and/or tag documents, but we can use a Delicious-like service combined with the URLs for the documents in SVN (or similar).
Later I'm not so worried about diffs on the binaries since, as stated above, they won't change much. I'm OK with a slight hassle if they do -- it's no worse than SharePoint.
Solution 1:
In my previous company we setup Subversion to store CAD files. Files upto 100 MB were stored in Subversion. If many people 'add' big files to Subversion webserver can be a bottleneck. However, incremental commits were perfectly ok.
Subversion stored 'binary delta'. In fact, on server side, binary and text files are treated exactly same in storing the 'delta'. Check "binary delta encoding improvements' section on page http://subversion.tigris.org/svn_1.4_releasenotes.html. It explicitly says "Subversion uses the xdelta algorithm to compute differences between strings of bytes" (and not strings of 'characters').
Just for experiment, I stored the 10 version of CAD (CATIA part file). Each version I made minor modifications to part and then check the serverside repository size. The total size was about 1.2x for about 10 revision (x - being the original file size).
Remember to set svn:needs-lock property. In my experience, Best way is to use 'auto props' to set the svn:needs-lock based on file extension.
Solution 2:
There's a difference between lots of big binary files, and a big number of binary files.
In my experience SVN is fine with individual binary files of several hundred megabytes. The only problems I've seen begin to occur with individual files of around a gigabyte or so. Operations fail for mysterious and unknown reasons, possibly SVN failing to handle network related problems.
I am not aware of any SVN problems related to the number of binary files, beyond their lack of merge-ability and the fact that binary files often can't be efficiently stored as deltas (SVN can use deltas).
So;
- 1000 1MB files = fine.
- 100 10MB files = fine
- 10 100MB files = fine
- 1 >1000MB file = not a good idea.
I would hope the size of your documents fits into one of the fine categories :)