When project that polls for multiple branches (like '**') is created, jenkins spawns a build for each existing leaf branch in repository.

When repository contains dozens of such branches (like for example monthly release patch branches that are leaves because commits were cherry-picked from master), jenkins would need several hours or maybe days to build them all, and there is no option to stop it from doing that.

It would be nice if git plugin could ignore SHA1s that had already existed in the repository during the project creation (probably should be easy to implement - just mark all the existing branches as already built), so that it would spawn builds only for commits that appear after the creation.

Alternative approach could be ignoring commits older then some configurable date, however it might be a bit risky, if you consider the fact that committer can set the commit date to any value in past or future in purpose or by accident.