On Fri, May 03, 2019 at 10:49:17PM +0200, Johannes Schindelin wrote:

I am well aware of the way Debian-based systems handle alternatives, and I
myself also use something similar to write this E-Mail (but it is not a
symlink, it is a Git alias).

But that's not the hack that I was talking about.

The hack I meant was: if you symlink `gzip` to `pigz` in your `PATH` *and
then expect `git archive --format=tgz` to pick that up*.

As far as I am concerned, the fact that `git archive --format=tgz` spawns
`gzip` to perform the compression is an implementation detail, and not
something that users should feel they can rely on.

I'd agree with you more if we didn't document a user-facing config
variable that claims to run "gzip" from the system.

quoted

Just commenting on the overall thread: I like René's "new built-in"
patch best.

I guess we now have to diverging votes: yours for the `git archive --gzip`
"built-in" and Peff's for the async code ;-)

For the record, I am fine with any of the solutions (including just
doing the single-thread bit you already have and letting René do what he
likes on top).

-Peff