Re: [PATCH 7/9] fetch: fetch submodules in parallel

On Fri, Aug 28, 2015 at 11:44 AM, Jeff King [off-list ref] wrote:

On Fri, Aug 28, 2015 at 11:41:17AM -0700, Stefan Beller wrote:

quoted

quoted

So to an observer, it would look like a serial operation, but subsequent
operations after the first would magically go much faster (because
they'd been working and buffering in the background).

And that doesn't require any additional IPC magic (though I am not sure
how we get progress in the first place if the child stderr is a
pipe...).

Moving the contents from the pipe to a strbuf buffer which we can grow
indefinitely
(way larger than pipe limits, but the output of a git fetch should be
small enough for that).

Right, clearly we can't rely on pipe buffers to be large enough here
(though we _may_ want to rely on tempfiles if we aren't sure that the
stdout is bounded in a reasonable way).

But what I meant was: the child will only show progress if stderr is a
tty, but here it is not.

Oh, I forgot about that.

I wonder if we need to set GIT_STDERR_IS_TTY=1 in the parent process,
and then respect it in the children (this is similar to what
GIT_PAGER_IN_USE does for stdout).

The use of GIT_PAGER_IN_USE looks straightforward to me. I'll try to add
GIT_STDERR_IS_TTY then.

-Peff