Git (revision control): Is it possible to pull more than one repository at the same time?

A new way to remap multiple Git repositories into one is Perforce Git Fusion.  You can define a new, virtual Git repo that contains the same content and history as the "subdirectory" projects. From the Git client point of view, this works like one big repo, and developers do not need to use submodule or subtree commands.  (You can also split out parts of an existing repo, or do whatever remixing you need.) When you push into the remapped repo, you can pull the same work into the original ones, which is useful if you want to contribute upstream or pull in a new version from a contributor at GitHub. More info: http://www.perforce.com/blog/121001/improving-git-experience-everyone (I am a regular Git user and employed as Technical Marketing Manager at Perforce Software.)

If your goal is simply parallelism and not coordination, you can just run them all in parallel from the shellscript. (If you need to coordinate versions, that's what 'git modules' are for). for i in [a b c d e]; do ( echo Pulling "$i" cd "$i" git pull )& BG="${BG} $!" done wait $BG echo Done

One of the big performance overheads of what you're doing is the need to constantly spawn and authenticate new SSH connections for each logical repository.There's an easy way to make this much, much more efficient.Add these two lines to the top of your ~/.ssh/config ControlMaster auto ControlPath ~/.ssh/control/%r@%h:%p What this does is it enables SSH to multiplex a single connection as long as the username, host and port values are the same ( which they are for github, they're all [email protected]:22 )Then, before doing your pull work, you spawn  a "master" background SSH connection. ssh -fNn [email protected] This creates a tty-less connection to github, and the "ControlMaster auto" in your means any subsequent connections to the same server will just re-use the existing one.So, lets compare:Normal: time ssh [email protected] Hi kentfredric! You've successfully authenticated, but GitHub does not provide shell access. real 0m2.925s user 0m0.034s sys 0m0.004s cpu 1.29% Setting up the connection: time ssh -fNn [email protected] real 0m2.613s user 0m0.045s sys 0m0.008s cpu 2.02% Now trying it with a pre-multiplexed connection: time ssh [email protected] Hi kentfredric! You've successfully authenticated, but GitHub does not provide shell access. real 0m0.447s user 0m0.002s sys 0m0.005s cpu 1.56% That just saved more than â…”rds  of the connection overhead.The only thing you have to worry about with this configuration is its unwise to do it on a shared resource, because it removes the authentication step from the connection setup, meaning anyone who can read your ~/.ssh/control/ path ( that is, you, and any programs you're running, whoever is root, and anyone who can sudo to you ) can potentially access any servers you've authenticated against before starting the master connection.If you want to limit this exposure so it only applies vs github, then you should move the Control statements statements to occur in a host-specific way only, by placing them under a Host github.com statement.Read man ssh_config for more details.

I've used mr (http://myrepos.branchable.com/ github https://github.com/joeyh/myrepos) for this.  It's not hugely powerful, but it's easy to use, free and open source).