We want to do some performance optimizations on our local SVN server (like moving to a better server, adding an SSD, etc...)
Is there some benchmark I could use to see if these modifications actually help performance?
Yes, there is one (published by CollabNet) -- https://ctf.open.collab.net/sf/projects/csvn/
In SVN server 1.8.0 fsfs-stats and svn-bench were introduced. The CollabNet install does not include them at the moment.