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This entire topic may be related to the way you use tags: for instance, we are pushing tags immediately on creation, because we consider tags to be server-side always and don't have "local tags". Anything which is local will be a branch.

Since 18.1 preview 2, SmartGit is using "git merge --abort" now which should resolve this problem.

According to Lars Schneider's comment, "git lfs clone" is obsolete now. http://smartgit.userecho.com/topics/65-gui-for-git-lfs/

Please give more details on performance problems: do you have a comparison for the same repository with and without junctions?