It's worth going through old HN comment sections that have flamewars of SVN v git (or cvs vs hg or whatever) from 2006-2012 or so. The dvcs systems won because they changed a bad paradigm to one that's much much better - literally the way you think about version control these days is a radical departure from the previous way it was done. Merges are much much nicer in git then they ever were in those old systems - I've never spent more than an hour dealing with the results of git issues, but I've lost literal weeks to a single svn mishap.
Why did git win over other dvcs systems?
2 main reasons I see:
1. Linux uses it - literally, that means its the "cool one"
2. Linux uses it - and that means the people developing it work similar to the kernel, they are willing to try a lot of different ways to acheive the task resulting in both some amazing cool stuff and a lot of cruft left hanging out for various compatability and "accidentally super important structurally" reasons.
There's a lesson here, too. To unseat git, you need to not just be slightly better than it; you need to have a big use case for many people and be radically better than it in that particular use case. You even can be worse than git in some others as long as you have that radical improvement to build on.
Being merely better isn't enough; see mercurial.
The use case actually has to be important to people in real life, too, not just be something that sounds cool or people might say is important but they don't actually exert any effort towards implementing; see fossil.
The problem is that it's not clear what that will be. It wasn't hard to tell branch merging was a huge weak spot of SVN even if you were close enough to it to not see the forest for the trees. What is git's weak spot? People might jump up to say "interface!" but the reality is, no, it's not; again see mercurial. Talk is cheap and complaints are cheaper but the reality is the community is not switching en masse because of that. Large binary files is certainly a weak spot and I understand there are some commercial solutions for that that edge out git, but that's not going to edge out git in general because the pain isn't enough for most projects, and while git-lfs isn't necessarily the slickest solution ever it's good enough for programming projects. Submodules are awful but it's not clear to me that there is enough pain there to make people switch even if you made that slick as can be. (Plus, if something did start eating git's lunch because of that, there are improvements git can make that would blunt the impact. Git's fundamental model means submodules are always going to be weird but it doesn't have to be as bad as it is. I think backwards compatibility prevents git from fixing the problems but if something was really a threat it could overcome that and they'd be improved.)
I expect to still be using git for many many years yet.
Well said, but I humbly disagree that it has to be better in some way, just easier AND as technically sound. Unless that is by your definition better. Ease of use is probably one of the most important factors in real life in determining preferences for software.
I strongly feel if someone could match the merging ability of Git with the ease of simple, well worded commands, it could win. And it doesn't even have to be a Git replacement, but a better frontend. Kind of how yay is to pacman. Or how most use something like Handbrake instead of ffmpeg.
In a lot of ways, it reminds me of Python and Perl. Perl was definitely more powerful as a language, but Python felt like natural writing in pseudocode. Enthusiasts rightly point to the power of inbuilt regex, but like Git, few actually could harness it well enough to make that unreadability worth it.
"I strongly feel if someone could match the merging ability of Git with the ease of simple, well worded commands, it could win."
But we have that, and not only didn't it win, it shows no sign of winning. Mercurial isn't even growing in apparent mindshare.
"Easier" and "technically sound" is by observation, not by a long line of strained theorizing, not enough. Theories must take this fact into account or be useless in explaining the real world.
But almost nobody actually uses git the way it was originally intended, eg. as decentralized version control? Instead there’s a canonical master repository (on GitHub) everyone pulls from/pushes to.
That your commits are made locally, in a clone of the entire repository, is decentralized. Your local respiratory accrues history as divergent (and unbeknownst) from upstream as you'd like it to.
If you're going to collaborate in a decentralized way you ultimately need an accepted mainline source of truth.
Everyone uses it the way it was intended. There's not really another option. Any time you create a branch locally, without needing to contact the central server you are using distributed vcs. Same when you do local commits, or rebases or whatever. All of that is because you have a local copy of the repo and history, and can develop your way against your local repo then push the resulting changes upstream. The fact that this allows chaining of upstreams is not the main focus of "decentralized" wrt git and the other dvcs, that's just a side effect of the concept that appealed to Linus since it would better fit the kernel development model.
From the point of view of someone stuck on subversion, all of that is freaking magic. This is what I mean about "radical departure". By analogy, there's people who think of horses as slower cars and say things like "why can't we just start using horses again" without ever considering the horse issues that are no longer relevant like: having to feed them every day, having to not ride them too long without resting the horse, what do to with all the poop, and so on because cars don't even have analogous impediments.
"Everyone" uses GitHub as a single source of truth, but I believe that git itself was not designed with this in mind. GitHub users use git as centralised version control with "local commits, rebases or whatever".
> Any time you create a branch locally, without needing to contact the central server you are using distributed vcs. Same when you do local commits, or rebases or whatever.
I think that it is possible to add local branches and commits to centralised version control. Will it make it decentralised? I don't think so.
> From the point of view of someone stuck on subversion, all of that is freaking magic. This is what I mean about "radical departure". By analogy, there's people who think of horses as slower cars and say things like "why can't we just start using horses again" without ever considering the horse issues that are no longer relevant like: having to feed them every day, having to not ride them too long without resting the horse, what do to with all the poop, and so on because cars don't even have analogous impediments.
It's not a topic of "horses vs cars" you know. Not even close. This analogy is a plain trolling IMO.
> I think that it is possible to add local branches and commits to centralised version control
Well, you think wrong, because it's not. Centralized change control will contact the central server for every change.
If you can make local commits, it's decentralized source control. Prove me wrong: show in the SVN or p4 or CVS documentation where you can create local branches or commits while the central server isn't reachable over the network
I believe that - hypothetically - centralised version control can have disconnected local commits with private local branches.
But using GitHub as a single source of truth for git repositories makes git mostly centralised. Think of it as of SVN with local commits and a central repository on GitHub (with its UI). And with awkward git’s CLI.
I don’t think that SVN, p4 or CVS have support for local commits. What I want to say is that local commits could be added into centralised version control systems. Come on, SVN has a local working copy. Won’t it handle local commits?
I think you are getting confused about what is decentralized by git (et al). It's not that there's a notion of "a canoncial copy". The canonical copy stuff is about user/developer organization. What dvcs distributes is the history - the notion that you can have local commits, branches, etc is a decentralization of a repo's history. In a centralized vcs, that history is always mediated by the server - you want a new revision number, you have to ask the server what it is.
The fact that you keep coming back to github to "prove" it's somehow centralized at the vcs level is clearly you just doing some contrarian trolling.
> In a centralized vcs, that history is always mediated by the server - you want a new revision number, you have to ask the server what it is.
I assume the most trivial case when say I contribute to e.g. MS documentation, which source is now available exclusively on GitHub. Can I say that this MS docs repository is a canonical copy?
I think that the most common daily use workflows with git and GitHub are absolutely centralised regardless of the decentralised nature of git.
* I have a local git repository, its local version history and all the great features this provides. But I have to push to GitHub, you know. Can I somehow publish my changes if GitHub is down? So how is this different from centralised version control?
* GitHib provides extra features besides version control. It has a bug tracker, wiki, whatever. I'm tied to all these features, and they are not decentralised at all. I understand that this analogy is silly, but GitHub is a well done SourceForge with Git. But it's still SourceForge, and it's centralised.
When I use git with GitHub, I usually only clone, commit and push and check my project's issue tracker. All these actions except commit require access to GitHub. So I think that the workflow is absolutely centralised even if git is decentralised by design and has local version history.
I think that's what @evouga meant in his comment above when he said > But almost nobody actually uses git the way it was originally intended, eg. as decentralized version control? Instead there’s a canonical master repository (on GitHub) everyone pulls from/pushes to.
There is (was?) an effort to do this, called SVK. [1]
I've used it before Git. While it wasn't good as Git, it actually worked pretty decently for staging changes in local prior to push.
> Instead there’s a canonical master repository (on GitHub) everyone pulls from/pushes to.
The company I work for has internal forks/clones of many projects hosted on GitHub.
I routinely interact with at least four different clones of a project: the upstream one on GitHub; the local one on my machine; my personal clone on GitHub for upstream contributions; and the company-internal clone hosted on some company-internal server.
So yes, we are using git in a decentralized fashion.
It might not be more decentralized in practice, but it's easier to make and accept outside contributions. Before "pull requests" were a thing there was the "patch" command. I don't miss manually figuring out how many directory levels to strip to get a patch to apply, or figuring out what to do when patch says "applied 7 of 9 hunks" or whatever.
Sure there was, it was called stash (and then that was bought by atlassian becoming bitbucket). You could host mercurial repos there until just a few years ago.
And at that point, even the use of dvcs was in question, so you could use svn on google's forge, or sourceforge. Launchpad had bzr support too.
It wasn't clear github was going to win until it was clear that git was going to win.
Google Code also had hg support before it had git support, if I remember right. Certainly the SVN -> hg migration was easier than SVN -> git if you were using it.
At the time I’m talking about that was a proprietary forge for bzr, Canonical’s unnecessary version of baz, which was the community fork of tla, which was the GNU experiment in DVCS with an even worse interface than git.
It's worth going through old HN comment sections that have flamewars of SVN v git (or cvs vs hg or whatever) from 2006-2012 or so. The dvcs systems won because they changed a bad paradigm to one that's much much better - literally the way you think about version control these days is a radical departure from the previous way it was done. Merges are much much nicer in git then they ever were in those old systems - I've never spent more than an hour dealing with the results of git issues, but I've lost literal weeks to a single svn mishap.
Why did git win over other dvcs systems?
2 main reasons I see:
1. Linux uses it - literally, that means its the "cool one"
2. Linux uses it - and that means the people developing it work similar to the kernel, they are willing to try a lot of different ways to acheive the task resulting in both some amazing cool stuff and a lot of cruft left hanging out for various compatability and "accidentally super important structurally" reasons.