Re: [Gnu-arch-users] Some issues

[Cameron Patrick]

Andrew Suffield wrote:

| > The changeset format is defined relative to GNU patch and GNU
| > tar. These data formats are still somewhat in flux.
| 
| What? I'm not aware of anything more stable than these.

tla requires specific versions of diff and patch to work.  That
suggests to me that their output format isn't particularly
well-defined or stable (or perhaps that earlier versions had bugs,
which amounts to the same thing).

| > The changeset format does not handle binaries efficiently, and
| > certain text files (e.g. XML files not created by a text editor and
| > formated for readability).
| 
| Right, nothing does. Unsolved problem. Nothing to do with
| tla. Supporting this would be fairly easy if the problem were ever
| solved.

We could do better than we do now, though.  Something like rdiff or
xdelta would be more efficient for some binary files.  We could grok
gzip/zip/bzip2 files and store some kind of patch based on the
compressed data.  Having said that, I'm not sure that any of this is
worth the extra complexity.

| > Categories, branches, and versions are not orthogonal at all and add
| > unnecessary complexity. Future features cannot differentiate between
| > them because they are used very inconsistently in existing archives.
| 
| No idea what that is supposed to mean. They're just names. Almost
| everything just wants a version specifier, and doesn't care about the
| fact that the '--'s in the string have significance.

I /think/ the complaint was that arch is enforcing unnecessary
structure on version/branch names.  Sometimes that structure is good,
sometimes it's bad.

| > The archive format optimizes for access to early versions, not most
| > recent ones as one would expect.
| 
| False. The archive format doesn't optimise for anything.

Yes, of course it does.  I'd say it optimises for simplicity and
robustness, myself.  Different ways of storing data can affect how
efficient different access patterns are.  CVS and svn make getting the
most recent revision O(1) whereas for tla it's O(n).

Cameron.