From: Junio C Hamano Date: Thu, 19 Mar 2015 19:24:21 GMT Subject: Re: Why is "git fetch --prune" so much slower than "git remote prune"? Message-ID: In-Reply-To: <550AE1E4.7020407@alum.mit.edu> Michael Haggerty writes: >> Now that we have ref_transaction_*, I think if git-fetch fed all of the >> deletes (along with the updates) into a single transaction, we would get >> the same optimization for free. Maybe that is even part of some of the >> pending ref_transaction work from Stefan or Michael (both cc'd). I >> haven't kept up very well with what is cooking in pu. > > I am looking into this now. > > For pruning, we can't use a ref_transaction as it is currently > implemented because it would fail if any of the reference deletions > failed. But in this case I think if any deletions fail, we would prefer > to emit a warning but keep going. I am not quite sure what you mean here. I agree with you if you meant "we shouldn't fail the fetch only because 'fetch --prune' failed to remove only one of the remote-tracking refs that are no longer there" but that can easily be solved by the pruning phase into a separate transaction. If you meant "we would rather remove origin/{a,b} non-atomically when we noticed that origin/{a,b,c} are all gone than leaving all three intact only because we failed to remove origin/c for whatever reason", my knee-jerk reaction is "does it make practical difference to the end user between these two?" What are the plausible cause of failing to prune unused remote-tracking refs?