Re: upload-pack is slow with lots of refs

Ævar Arnfjörð Bjarmason [off-list ref] writes:

I'm creating a system where a lot of remotes constantly fetch from a
central repository for deployment purposes, but I've noticed that even
with a remote.$name.fetch configuration to only get certain refs a
"git fetch" will still call git-upload pack which will provide a list
of all references.

It has been observed that the sender has to advertise megabytes of
refs because it has to speak first before knowing what the receiver
wants, even when the receiver is interested in getting updates from
only one of them, or worse yet, when the receiver is only trying to
peek the ref it is interested has been updated.

I do not think upload-pack that runs on the sender side with
millions refs, when asked for a single "want", feeds all the refs
that it has to the revision machinery, and if you observed it does,
I cannot explain why it happens.