Re: [Gnu-arch-users] GNU Arch 2.0 -- first source

[Clark McGrew]

On Sun, 2005-07-10 at 17:45 +0400, nick wrote:
> Thomas Lord wrote:

> > The first source release and some very early documentation for Arch 
> > 2.0 ("revc") is now ready!
> 
> I have tried 'revc'.
> But I have some question.
> Why changed files have stored in revc archieve as full content?
> Tla in such case have less space consume.
> I have project with small number of big text files that modify in every 
> commit and revc doesn't seems resonable for me.
> Maybe try to resolve space consuming problem while revc is alfa stage?

I agree with others that saving full files in a change set is probably
not a problem most of the time for most users, but that implies it is a
problem some of the time for some users.  It seems that the current
manifest format could be easily extended to allow both full file and
delta changes.  

>From what I can tell a single record in the manifest consists of a file
name/sha1 key pair that maps file content to file name.  If the manifest
were extended to allow a file name, an sha1 key for the base content,
plus a series of sha1 keys for deltas applied to the base, then users
could have the best of both worlds.  The basic revc-commit would remain
unchanged, and users who want delta-compression for particular commits
could use a supplemental command (say revc-commit-delta).  This adds a
little bit of complexity, but at first naive glance, it would seem to be
isolated in the code that maps the filename/sha1 pair into actual file
content.

-Best, 

Clark

-- 
Clark McGrew                    Univ. at Stony Brook, Physics and Astronomy
<address@hidden>   631-632-8299