| Jonathan Rogers the textual description of git clone is that it is the combination of git fetch and git merge. However, we've also had reports from a few Jenkins users that they also see faster performance if they use git clone instead of the git fetch which is used by the git plugin. When I attempted to duplicate the performance difference in that case, I was unable to do so. At that time, I consistently found comparable performance when comparing git clone and git fetch + git merge. That likely means that I don't understand the specific details which cause clone to be faster than fetch. Unfortunately, the connection between fetch and the use cases of the git plugin are strong enough that I don't think there will ever be a way to call git clone directly from the plugin. The change from clone to fetch would break many different use cases. As one example, I've seen much better performance if I specify a narrow refspec to the git plugin. The multibranch pipeline code uses that technique to limit a clone to a single branch, rather than cloning all branches in the repository. The narrow refspec limits the amount of information sent from the remote to the local to only the specific named branch. Unfortunately, the git clone command doesn't accept a refspec as an argument. There are command line arguments that will allow adding more refspecs, but there is no way to limit the refspec from the clone command line. |
