Interesting that multiple people are noticing this same thing. For me, this could have been:
"We found that a large portion of the 48 hours taken to backup our rails respository was due to a function in `git bundle create` that checks for duplicate references entered as command line arguments. The check contained a nested for loop ( O(N2) ), which we replaced with a map data structure in an upstream fix to Git. The patch was accepted, but we also backported fix without waiting for the next Git version. With this change, backup time dropped to 41 minutes."
"We found that a large portion of the 48 hours taken to backup our rails respository was due to a function in `git bundle create` that checks for duplicate references entered as command line arguments. The check contained a nested for loop ( O(N2) ), which we replaced with a map data structure in an upstream fix to Git. The patch was accepted, but we also backported fix without waiting for the next Git version. With this change, backup time dropped to 41 minutes."