svnsync: Revision being currently copied, last merged revision, and destination HEAD are inconsistent

I run the following command:

svnsync synchronize svn://www.example.com/repos
svnsync: Revision being currently copied (19931), last merged revision (19929), and destination HEAD (19931) are inconsistent; have you committed to the destination without using svnsync?

And then I run it again 30 seconds later:

svnsync synchronize svn://www.example.com/repos
svnsync: Revision being currently copied (20012), last merged revision (20010), and destination HEAD (20011) are inconsistent; hav开发者_如何学运维e you committed to the destination without using svnsync?

I don't understand why, if its "blocked", are the numbers increasing?

I'm doing the above as root, and no jobs or processes are running (and root is the only user account).

For your process, when you use a svnadmin load the primary repository should be locked. This process checks if the last merged revision are equal for a sync to commence.