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moving to svn?

Rafael Espíndola
Just wondering: Is there any plan to move to svn? I would love to have
a diff command that works when I am offline :-)

Best Regards,
Rafael
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Re: moving to svn?

Reid Spencer-2
Rafael,

On Mon, 2006-11-27 at 16:05 -0300, Rafael Espíndola wrote:
> Just wondering: Is there any plan to move to svn? I would love to have
> a diff command that works when I am offline :-)

Its been discussed from time to time. I would like to see this as well,
but for an additional reasons: simpler branch management and faster
updates, etc. SVN handles directories better and merging head to/from a
branch is much easier (no tagging required because it remembers the
merges).

Unfortunately, this is a pretty big change. The main issues are:
1. retention of original log
2. converting the post-commit scripts
3. Subversion isn't fully distributed and if we're going to change, is
SVN really the
   best choice?

Reid.

>
> Best Regards,
> Rafael
> _______________________________________________
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Re: moving to svn?

Chris Morgan-2
> Its been discussed from time to time. I would like to see this as well,
> but for an additional reasons: simpler branch management and faster
> updates, etc. SVN handles directories better and merging head to/from a
> branch is much easier (no tagging required because it remembers the
> merges).
>

I'm not sure what you mean here by merge tracking but merge tracking
in SVN is under development but not yet complete or available in a
supported release.

Chris
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Re: moving to svn?

Scott Michel
In reply to this post by Reid Spencer-2
Reid Spencer wrote:

> Rafael,
>
> On Mon, 2006-11-27 at 16:05 -0300, Rafael Espíndola wrote:
>
>>Just wondering: Is there any plan to move to svn? I would love to have
>>a diff command that works when I am offline :-)
>
>
> Its been discussed from time to time. I would like to see this as well,
> but for an additional reasons: simpler branch management and faster
> updates, etc. SVN handles directories better and merging head to/from a
> branch is much easier (no tagging required because it remembers the
> merges).
>
> Unfortunately, this is a pretty big change. The main issues are:
> 1. retention of original log
> 2. converting the post-commit scripts
> 3. Subversion isn't fully distributed and if we're going to change, is
> SVN really the
>    best choice?

Look into tailor (http://darcs.arstecnica.it/). It works well with
converting repositories as well as running those repos in parallel until
the official cutover. Granted, you might need darcs to pull the current
version out of its repo, since it was originally designed with darcs in
mind. Nonetheless, it works rather well.


-scooter
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Re: moving to svn?

Rafael Espíndola
In reply to this post by Reid Spencer-2
> Its been discussed from time to time. I would like to see this as well,
> but for an additional reasons: simpler branch management and faster
> updates, etc. SVN handles directories better and merging head to/from a
> branch is much easier (no tagging required because it remembers the
> merges).
Yes. This is very nice. Atomic commits are also usefull for finding
the patch that introduced or fixed a bug.

> Unfortunately, this is a pretty big change. The main issues are:
> 1. retention of original log
> 2. converting the post-commit scripts
> 3. Subversion isn't fully distributed and if we're going to change, is
> SVN really the
>    best choice?
I have just created a copy of the llvm-gcc repository using svk and I
like it! It should also be easier to move from cvs to svn then to git
for exemple.

> Reid.

Rafael
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Re: moving to svn?

Reid Spencer-2
In reply to this post by Chris Morgan-2
On Mon, 2006-11-27 at 15:22 -0500, Chris Morgan wrote:

> > Its been discussed from time to time. I would like to see this as well,
> > but for an additional reasons: simpler branch management and faster
> > updates, etc. SVN handles directories better and merging head to/from a
> > branch is much easier (no tagging required because it remembers the
> > merges).
> >
>
> I'm not sure what you mean here by merge tracking but merge tracking
> in SVN is under development but not yet complete or available in a
> supported release.

Sure, the full merge tracking functionality isn't available (yet), but
its definitely easier to keep track of with subversion.  In any event,
its not likely to change in the near future. I suppose this could be a
topic for LLVM Conference 2007 :)

Reid.

>
> Chris
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Re: moving to svn?

Anton Korobeynikov
In reply to this post by Reid Spencer-2
Hello, Scott.

> the official cutover. Granted, you might need darcs to pull the current
> version out of its repo, since it was originally designed with darcs in
> mind.
I can confirm, that tailor converts LLVM CVS with all history preserved
to mercurial repository without any visible troubles.

--
With best regards, Anton Korobeynikov.

Faculty of Mathematics & Mechanics, Saint Petersburg State University.


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Re: moving to svn?

Devang Patel
In reply to this post by Chris Morgan-2

On Nov 27, 2006, at 12:22 PM, Chris Morgan wrote:

>> Its been discussed from time to time. I would like to see this as  
>> well,
>> but for an additional reasons: simpler branch management and faster
>> updates, etc. SVN handles directories better and merging head to/
>> from a
>> branch is much easier (no tagging required because it remembers the
>> merges).
>>
>
> I'm not sure what you mean here by merge tracking but merge tracking
> in SVN is under development but not yet complete or available in a
> supported release.

svnmerge.py makes it easy. [ http://gcc.gnu.org/wiki/SvnBranch ]

-
Devang

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Re: moving to svn?

Óscar Fuentes-3
In reply to this post by Reid Spencer-2
Reid Spencer <[hidden email]> writes:

> Its been discussed from time to time. I would like to see this as well,
> but for an additional reasons: simpler branch management and faster
> updates, etc. SVN handles directories better and merging head to/from a
> branch is much easier (no tagging required because it remembers the
> merges).

SVN does no keep track of merges.

> Unfortunately, this is a pretty big change. The main issues are:
> 1. retention of original log

No problem. cvs2svn and tailor will keep full log info.

> 2. converting the post-commit scripts
> 3. Subversion isn't fully distributed and if we're going to change, is
> SVN really the
>    best choice?

Others mentioned svk, which is compatible with svn and is fully
distributed. However, if distributed VCS is really interesting for
you, I highly recommend Mercurial:

http://www.selenic.com/mercurial/wiki/index.cgi

BTW, tailor works nicely for converting CVS repos to Mercurial.

--
Oscar

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Re: moving to svn?

Scott Michel
In reply to this post by Anton Korobeynikov
Anton Korobeynikov wrote:
>>the official cutover. Granted, you might need darcs to pull the current
>>version out of its repo, since it was originally designed with darcs in
>>mind.
>
> I can confirm, that tailor converts LLVM CVS with all history preserved
> to mercurial repository without any visible troubles.

I'm not sure if I just took HEAD or converted the whole llvm repo.
Personally, I like darcs for the atomic theory of patches. YMMV.

Nonetheless, I track llvm's repo via tailor and I do keep the history as
it evolves. If I were permitted to run a webserver outside the corporate
firewall, I'd demonstrate a cvs-svn tailor-ized repo.


-scooter

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Re: moving to svn?

Daniel Berlin
On 11/27/06, Scott Michel <[hidden email]> wrote:

> Anton Korobeynikov wrote:
> >>the official cutover. Granted, you might need darcs to pull the current
> >>version out of its repo, since it was originally designed with darcs in
> >>mind.
> >
> > I can confirm, that tailor converts LLVM CVS with all history preserved
> > to mercurial repository without any visible troubles.
>
> I'm not sure if I just took HEAD or converted the whole llvm repo.
> Personally, I like darcs for the atomic theory of patches. YMMV.
>

DARCS is ridiculously slow on large repositories.

SVN is usable.
Mercurial is usable, though if you try to keep a lot branches in a
single repository space, it will fall down right now because it
creates at least one file in the repo per file in the tree (this would
require close to 400k files for gcc , IIRC:P).  This is typical of
most distributed systems, contrary to the claims that they easily
support centralized models.

At least in mercurial, this is easy to fix because of how the
repository format works (it would probably take about 6  weeks of
engineer time ).

Bottom line:
If your goal is a distributed VCS use Mercurial
If your goal is a centralized VCS, use SVN

Bias: I am a subversion developer, and responsible for moving GCC from
CVS to SVN :)

I use SVK to track GCC nowadays, and find it quite easy.  However, I
still don't believe GCC would work in a project if we didn't have a
centralized server with a single namespace/repository for all
branches.   This does not, of course, mean it can't be a mercurial
server in a few years.  :)



> Nonetheless, I track llvm's repo via tailor and I do keep the history as
> it evolves. If I were permitted to run a webserver outside the corporate
> firewall, I'd demonstrate a cvs-svn tailor-ized repo.
>
>
> -scooter
>
> _______________________________________________
> LLVM Developers mailing list
> [hidden email]         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>
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Re: moving to svn?

Rafael Espíndola
In reply to this post by Scott Michel
> I'm not sure if I just took HEAD or converted the whole llvm repo.
> Personally, I like darcs for the atomic theory of patches. YMMV.

I have used darcs to work with psi. It looks like a very clean design,
but currently it is a very anemic implementation IMHO. I constantly
find myself trying to find out how to do a relatively simple task.

Git is fast and has a lot of features, but eats hard disk for lunch :-)

In the end, I think that the best option now would be to move to svn.
If we want to move to another SCM system latter on, the move should be
much simpler then the cvs -> svn move.

Another wonderful feature of svn: each commit generates a single email
to llvm-commits :-)

> Nonetheless, I track llvm's repo via tailor and I do keep the history as
> it evolves. If I were permitted to run a webserver outside the corporate
> firewall, I'd demonstrate a cvs-svn tailor-ized repo.
>
>
> -scooter

Rafael
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Re: moving to svn?

Scott Michel
In reply to this post by Daniel Berlin
To (mis)quote a colleague, "All version control systems suck, but <foo>
sucks less." (my appologies to Mike Elkins)

darcs works for me. darcs sucks less.

Before this devolves into another "my vcs is is bigger, better, faster
and has whiter teeth" rat hole, I was merely pointing out that there are
ways to convert the current CVS repo intact.

Frankly, converting to svn means that I merely have to edit my tailor
configuration.

Daniel Berlin wrote:

> On 11/27/06, Scott Michel <[hidden email]> wrote:
>
>>Anton Korobeynikov wrote:
>>
>>>>the official cutover. Granted, you might need darcs to pull the current
>>>>version out of its repo, since it was originally designed with darcs in
>>>>mind.
>>>
>>>I can confirm, that tailor converts LLVM CVS with all history preserved
>>>to mercurial repository without any visible troubles.
>>
>>I'm not sure if I just took HEAD or converted the whole llvm repo.
>>Personally, I like darcs for the atomic theory of patches. YMMV.
>>
>
>
> DARCS is ridiculously slow on large repositories.
>
> SVN is usable.
> Mercurial is usable, though if you try to keep a lot branches in a
> single repository space, it will fall down right now because it
> creates at least one file in the repo per file in the tree (this would
> require close to 400k files for gcc , IIRC:P).  This is typical of
> most distributed systems, contrary to the claims that they easily
> support centralized models.
>
> At least in mercurial, this is easy to fix because of how the
> repository format works (it would probably take about 6  weeks of
> engineer time ).
>
> Bottom line:
> If your goal is a distributed VCS use Mercurial
> If your goal is a centralized VCS, use SVN
>
> Bias: I am a subversion developer, and responsible for moving GCC from
> CVS to SVN :)
>
> I use SVK to track GCC nowadays, and find it quite easy.  However, I
> still don't believe GCC would work in a project if we didn't have a
> centralized server with a single namespace/repository for all
> branches.   This does not, of course, mean it can't be a mercurial
> server in a few years.  :)
>
>
>
>
>>Nonetheless, I track llvm's repo via tailor and I do keep the history as
>>it evolves. If I were permitted to run a webserver outside the corporate
>>firewall, I'd demonstrate a cvs-svn tailor-ized repo.
>>
>>
>>-scooter
>>
>>_______________________________________________
>>LLVM Developers mailing list
>>[hidden email]         http://llvm.cs.uiuc.edu
>>http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>>
>
> _______________________________________________
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> [hidden email]         http://llvm.cs.uiuc.edu
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Re: moving to svn?

Bill Wendling
In reply to this post by Rafael Espíndola
Perhaps someone could come up with a list of different versioning
software, list the pros and cons, and then we could vote? (Has anyone
mentioned Bitkeeper yet? :-)

-bw

On 11/28/06, Rafael Espíndola <[hidden email]> wrote:

> > I'm not sure if I just took HEAD or converted the whole llvm repo.
> > Personally, I like darcs for the atomic theory of patches. YMMV.
>
> I have used darcs to work with psi. It looks like a very clean design,
> but currently it is a very anemic implementation IMHO. I constantly
> find myself trying to find out how to do a relatively simple task.
>
> Git is fast and has a lot of features, but eats hard disk for lunch :-)
>
> In the end, I think that the best option now would be to move to svn.
> If we want to move to another SCM system latter on, the move should be
> much simpler then the cvs -> svn move.
>
> Another wonderful feature of svn: each commit generates a single email
> to llvm-commits :-)
>
> > Nonetheless, I track llvm's repo via tailor and I do keep the history as
> > it evolves. If I were permitted to run a webserver outside the corporate
> > firewall, I'd demonstrate a cvs-svn tailor-ized repo.
> >
> >
> > -scooter
>
> Rafael
> _______________________________________________
> LLVM Developers mailing list
> [hidden email]         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>

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Re: moving to svn?

Nick Lewycky
Bill Wendling wrote:
> Perhaps someone could come up with a list of different versioning
> software, list the pros and cons, and then we could vote? (Has anyone
> mentioned Bitkeeper yet? :-)

 From the maker of SLOCCOUNT: http://dwheeler.com/essays/scm.html

Nick
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Re: moving to svn?

Nate Begeman
In reply to this post by Bill Wendling
I vote for staying with CVS or moving to SVN, but there's just not  
that much wrong with the CVS repository now that warrants switching.  
Offline diffing would be nice, but is not crucial to development.  As  
for random non-cvs, non-svn version control systems, I'm casting a  
"no" vote since that would require that I install yet more software  
and learn yet another version control system.

Nate

On Nov 28, 2006, at 11:06 AM, Bill Wendling wrote:

> Perhaps someone could come up with a list of different versioning
> software, list the pros and cons, and then we could vote? (Has anyone
> mentioned Bitkeeper yet? :-)
>
> -bw
>
> On 11/28/06, Rafael Espíndola <[hidden email]> wrote:
>>> I'm not sure if I just took HEAD or converted the whole llvm repo.
>>> Personally, I like darcs for the atomic theory of patches. YMMV.
>>
>> I have used darcs to work with psi. It looks like a very clean  
>> design,
>> but currently it is a very anemic implementation IMHO. I constantly
>> find myself trying to find out how to do a relatively simple task.
>>
>> Git is fast and has a lot of features, but eats hard disk for  
>> lunch :-)
>>
>> In the end, I think that the best option now would be to move to svn.
>> If we want to move to another SCM system latter on, the move  
>> should be
>> much simpler then the cvs -> svn move.
>>
>> Another wonderful feature of svn: each commit generates a single  
>> email
>> to llvm-commits :-)
>>
>>> Nonetheless, I track llvm's repo via tailor and I do keep the  
>>> history as
>>> it evolves. If I were permitted to run a webserver outside the  
>>> corporate
>>> firewall, I'd demonstrate a cvs-svn tailor-ized repo.
>>>
>>>
>>> -scooter
>>
>> Rafael
>> _______________________________________________
>> LLVM Developers mailing list
>> [hidden email]         http://llvm.cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>>
>
> _______________________________________________
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Re: moving to svn?

Chris Lattner
In reply to this post by Bill Wendling
On Tue, 28 Nov 2006, Bill Wendling wrote:
> Perhaps someone could come up with a list of different versioning
> software, list the pros and cons, and then we could vote? (Has anyone
> mentioned Bitkeeper yet? :-)

There are a couple reasons we are using CVS still:

1. CVS works and is well understood by all involved.
2. The main deficiencies of CVS don't impact us much (we aren't
    hampered by lack of atomic commits, renames, and better branch
    facilities).
3. The CVS server is hosted at Illinois.  You will have to get buy in from
    them and a volenteer with access to the machine to do the upgrade work
    (including converting the post-commit hooks, etc).
4. I maintain that a real distributed VCS would be very useful for LLVM,
    perhaps moreso than the other features provided by new VCS's.  Last
    time this came up, the available distributed vcs's all had serious
    issues.  Perhaps mercurial is 'there now'.  I don't know.

Personally, I don't really care which VCS we use.  I use SVN with the
llvm-gcc stuff and it works fine.  CVS works fine.  I'm sure that, with
enough beating on it, some other system would work fine.

-Chris

--
http://nondot.org/sabre/
http://llvm.org/
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Re: moving to svn?

Ralph Corderoy

Hi Chris,

> 2. The main deficiencies of CVS don't impact us much (we aren't
> hampered by lack of atomic commits, renames, and better branch
> facilities).

If people would like to see the logical `patch set' that made up a CVS
commit then cvsps may be useful, or, as others have said, use Tailor to
convert to a local repos. in your preferred format.

    http://www.cobite.com/cvsps/
    http://www.darcs.net/DarcsWiki/Tailor

> 4. I maintain that a real distributed VCS would be very useful for
> LLVM, perhaps moreso than the other features provided by new VCS's.
> Last time this came up, the available distributed vcs's all had
> serious issues.  Perhaps mercurial is 'there now'.  I don't know.

Bazaar, from Canonical -- the same people as behind Ubuntu, has been
concentrating on performance recently.  It may be worth keeping an eye
on for the future.  I expect it will gain quite a large market share
over time.

    http://bazaar-vcs.org/
    http://bazaar-vcs.org/RcsComparisons

Cheers,


Ralph.


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Re: moving to svn?

Alkis Evlogimenos-2
Perhaps code.google.com svn? The only thing that can be a problem is
the lack of support for commit scripts.

On 11/29/06, Ralph Corderoy <[hidden email]> wrote:

>
> Hi Chris,
>
> > 2. The main deficiencies of CVS don't impact us much (we aren't
> > hampered by lack of atomic commits, renames, and better branch
> > facilities).
>
> If people would like to see the logical `patch set' that made up a CVS
> commit then cvsps may be useful, or, as others have said, use Tailor to
> convert to a local repos. in your preferred format.
>
>     http://www.cobite.com/cvsps/
>     http://www.darcs.net/DarcsWiki/Tailor
>
> > 4. I maintain that a real distributed VCS would be very useful for
> > LLVM, perhaps moreso than the other features provided by new VCS's.
> > Last time this came up, the available distributed vcs's all had
> > serious issues.  Perhaps mercurial is 'there now'.  I don't know.
>
> Bazaar, from Canonical -- the same people as behind Ubuntu, has been
> concentrating on performance recently.  It may be worth keeping an eye
> on for the future.  I expect it will gain quite a large market share
> over time.
>
>     http://bazaar-vcs.org/
>     http://bazaar-vcs.org/RcsComparisons
>
> Cheers,
>
>
> Ralph.
>
>
> _______________________________________________
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>


--

Alkis
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Re: moving to svn?

Ted Kremenek
In reply to this post by Bill Wendling
On Nov 28, 2006, at 11:06 AM, Bill Wendling wrote:

> (Has anyone
> mentioned Bitkeeper yet? :-)

I'm not certain if this was a serious suggestion.  Probably not.  
I'll actually comment on this one because we actually do use  
BitKeeper in my research group.

It's a great tool, but it is not free anymore for open-source  
projects.  Branching and merging is a breeze in BitKeeper, has atomic  
commits, changesets, is completely designed for distributed  
development (a developer has complete access to all version control  
information on their local checkout of the repository without being  
connected to the Internet), and so on.

It also costs a lot, probably more than any version control software  
out there.  Although I cannot disclose how much we pay for it (and we  
have an academic license), if you came up with a figure in your head  
and multiplied it by two that would probably be far less than how  
much it costs to pay for a 1 year lease of BitKeeper.  That said, it  
is a great tool.
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