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Complexity of creating a new revision.

From: T'aZ <tazdev_at_punkass.com>
Date: 2005-10-23 17:30:01 CEST


I'm studying the complexity of various operations in svn

i'll take creating a new tag for example
i've understood that this results in a new revision tree and in this tree there is now a node poiting to revision X of a particular path

this operation is said to take a constant time
this is were a disagree , because according to http://subversion.tigris.org/files/documents/15/17/svn-design.html#Diffy%20Storage

the vector of trees is not stored as complete copies in the repository,
it's encoded as a series of "deltas"
so when you use the FSFS or the BDB backend, you have to read/adjust O(log(n)) deltas (according to svn/trunk/notes/skip-deltas )
so this is *not* done in constant time, right ?

an other question:
since accessing a given revision number costs O(log(n))
when we have this revision, nodes poiting to a different revision tree are not accessible, svn has to go again through O(log(n)) deltas , and this, for each nodes not directly accessible ?

thanks in advance for your answers :)

T'aZ |Jabber:taz-007_at_jabber.org|GPG keyID:E051925D|http://taz.prout.be
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Received on Sun Oct 23 17:37:56 2005

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