On Fri, Dec 18, 2009 at 8:08 AM, Ryan Schmidt
<subversion-2009d_at_ryandesign.com> wrote:
> On Dec 18, 2009, at 06:52, Andrew Hardy wrote:
> The presence of the revs directory indicates this is not a BDB repository but an FSFS one.
> FSFS is the default repository type since Subversion 1.2.
>
> The behavior you are observing in the revs directory is called sharding and is new for
> Subversion 1.5, and was improved in 1.6, and can lead to significant space savings:
Sharding does not specifically bring disk space saving, it just helps
some filesystem tools that slow down when you get too many files in a
single folder, like backup scanning or browsing tools like Windows
Explorer. It may bring some inode savings, but I am not sure.
>
> http://subversion.tigris.org/svn_1.6_releasenotes.html#fsfs-packing
Packing will save a lot of disk space by freeing up all the wasted
space in unused clusters, and will also greatly reduce inode usage.
However, packing is not something that happens automatically, you have
to run svnadmin pack.
The most likely culprit is the new rep-sharing feature in 1.6. This
allows duplicate "representations" to be shared. So imagine you
committed 5 copies of the exact same ISO image. With 1.6, only one of
those would be "stored" and the other 4 would all have pointers to the
first. We typically see a 10-20% space improvement from this, but it
is entirely dependent on how much common content there is. I would
guess this is where the saving came from since this is on by default
for a newly created repository.
--
Thanks
Mark Phippard
http://markphip.blogspot.com/
------------------------------------------------------
http://subversion.tigris.org/ds/viewMessage.do?dsForumId=1065&dsMessageId=2431501
Please start new threads on the <users_at_subversion.apache.org> mailing list.
To subscribe to the new list, send an empty e-mail to <users-subscribe_at_subversion.apache.org>.
Received on 2009-12-18 16:01:53 CET