home | list info | list archive | date index | thread index

Re: [OCLUG-Tech] does a DVCS *necessarily* mirror the entire repo history?

  • Subject: Re: [OCLUG-Tech] does a DVCS *necessarily* mirror the entire repo history?
  • From: "Robert P. J. Day" <rpjday [ at ] crashcourse [ dot ] ca>
  • Date: Fri, 23 Sep 2016 04:20:53 -0400 (EDT)
On Thu, 22 Sep 2016, Alex Pilon wrote:

> On Thu, Sep 22, 2016 at 07:43:34AM -0400, Robert P. J. Day wrote:
> >   (side note: currently updating all my git wiki pages and tutorials,
> > so i'll be asking a number of questions about git, including
> > apparently trivial ones that might not be so trivial.)
> Sweet.
> >   pro git book makes the claim:
> >
> > "In a DVCS (such as Git, Mercurial, Bazaar or Darcs),
> People still use the last two‽
> > clients don’t just check out the latest snapshot of the files: they
> > fully mirror the repository."
> >
> >   is that claim true in *every* case? as in, is there no "distributed"
> > VCS that doesn't necessarily mirror the entire repo that was cloned or
> > checked out?
> At least Git can do shallow clones, though that's not the normal use
> case.
> > i'm not sure how that would work but, theoretically, it might be
> > possible to still have some sort of distributed operation where
> > you don't have the entire repo history on your local machine.
> If distributed file sharing and filesystems exist, a PoC DVCS should
> be possible. How radically different of a departure from your Git
> workflow were you imagining? Just lazy but automatic retrieval of
> history from your remotes? Lazy push to your remotes? Seamless
> developer networks? Lazy server push to past clients? Sharding?
> More?
> Kiss goodbye to force push and history rewriting.

... snip ...

  i wouldn't want to try to change my workflow to accommodate those
changes either, i was just curious as to whether "DVCS" *necessarily*
implies full copy of history on local machine and, thus far, it would
seem to.


p.s. i've also never needed to do a shallow clone, but i tested that
last week on the linux kernel source repo, and cloning to a depth of
just 1 reduced size down to 10%. so maybe there's value for that if
one is *really* strapped for disk space or net bandwidth.


Robert P. J. Day                                 Ottawa, Ontario, CANADA

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday