Re: Question about your git habits

["J.C. Pizarro" <jcpiza@gmail.com>]

On 2008/2/23, Charles Bailey <charles@hashpling.org> wrote:
> On Sat, Feb 23, 2008 at 03:47:07AM +0100, J.C. Pizarro wrote:
>  >
>  > Yesterday, i had git cloned git://foo.com/bar.git   ( 777 MiB )
>  >  Today, i've git cloned git://foo.com/bar.git   ( 779 MiB )
>  >
>  >  Both repos are different binaries , and i used 777 MiB + 779 MiB = 1556 MiB
>  >  of bandwidth in two days. It's much!
>  >
>  >  Why don't we implement "binary delta between old git repo and recent git repo"
>  >  with "SHA1 built git repo verifier"?
>  >
>  >  Suppose the size cost of this binary delta is e.g. around 52 MiB instead of
>  >  2 MiB due to numerous mismatching of binary parts, then the bandwidth
>  >  in two days will be 777 MiB + 52 MiB = 829 MiB instead of 1556 MiB.
>  >
>  >  Unfortunately, this "binary delta of repos" is not implemented yet :|
>
>
> It sounds like what concerns you is the bandwith to git://foo.bar. If
>  you are cloning the first repository to somewhere were the first
>  clone is accessible and bandwidth between the clones is not an issue,
>  then you should be able to use the --reference parameter to git clone
>  to just fetch the missing ~2 MiB from foo.bar.
>
>  A "binary delta of repos" should just be an 'incremental' pack file
>  and the git protocol should support generating an appropriate one. I'm
>  not quite sure what "not implemented yet" feature you are looking for.

But if the repos are aggressively repacked then the bit to bit differences
are not ~2 MiB.