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Hi all,

We've noticed that when repos have been in use for a while by zuul-merger, they have a lot of left over objects that slow down git operations. Zuul-merger also seems to keep open a bunch of file handles to various objects, so running `git gc` on the repos seems dangerous, if they got deleted by `git gc` while zm has them open still, that might cause all sorts of trouble for zuul-merger, yes?

What's the safest way of doing gc on the repos? Or would this be a good feature to add to zuul-merger?

Thanks,
Nikki