On Wed, Aug 7, 2019 at 9:11 PM Phil Hord <phil.h...@gmail.com> wrote: > > From: Phil Hord <phil.h...@gmail.com> > > 'git tag -d' accepts one or more tag refs to delete, but each deletion > is done by calling `delete_ref` on each argv. This is painfully slow > when removing from packed refs. Use delete_refs instead so all the > removals can be done inside a single transaction with a single write.
Nice, thanks for working on this. > I have a repo with 24,000 tags, most of which are not useful to any > developers. Having this many refs slows down many operations that > would otherwise be very fast. Removing these tags when they've been > accidentally fetched again takes about 30 minutes using delete_ref. I also get really slow times on a repo with ~20,000 tags (though order ~3 minutes rather than ~30, probably due to having an SSD on this machine) -- but ONLY IF the refs are packed first (git pack-refs --all). If the refs are loose, it's relatively quick to delete a dozen thousand or so tags (order of a few seconds). It might be worth mentioning in the commit message that this only makes a significant difference in the case where the refs are packed. > git tag -l feature/* | xargs git tag -d > > Removing the same tags using delete_refs takes less than 5 seconds. It appears this same bug also affects `git branch -d` when deleting lots of branches (or remote tracking branches) and they are all packed; could you apply the same fix there? In constrast, it appears that `git update-ref --stdin` is fast regardless of whether the refs are packed, e.g. git tag -l feature/* | sed -e 's%^%delete refs/tags/%' | git update-ref --stdin finishes quickly (order of a few seconds).