RE: [Axiom-developer] build-improvements on cygwin

[Bill Page]

On November 28, 2006 11:30 AM Tim Daly wrote:
> 
> 
> > | And I can not obtain build-improvements from Google Code 
> > | because we long ago exceeded the maximum allowed capacity
> > | of that site
> > 
> > That was predictable.
> 
> I can see how you feel that way but I'm a bit puzzled.
> 
> Didn't google give us a full gig of disk space?
>

No. They eventually grudgingly "compromised" at 750MBMbytes.
See email from Ben Collins-Sussman below.

> I thought SVN only copies files when they are changed
> so branches should not be expensive since they store 
> only changes.

Yes, in theory. However when creating a mirror it seems that this
may or may not be the case. If the file systems are the same then
one can just rsync the files and the result is identical but
according to Ben, the version of SVN at Google Code uses some
new and different file system so simply copying the underlying
repository files is not an option. The last email I have from him
on this issue mentioned a possible problem with space allocation
or maybe a disk usage accounting error.

Also since then we have two new branches in the SourceForge SVN
repository. Apparently creating branches via the SVK mirror and
smerge commands does *not* conserve disk space.

And another thing is that since this is a repository and all
history is kept, everything we do takes more space. For example
each new version of gcl-2.6.8pre.tgz that we commit to the SVN
repository adds another 50 Mbytes since no attempt is made to do
binary diffs. (I think there are already 4 versions of gcl in the
build-improvements branch.)

> I know that GIT only copies files when the checksums differ so
> several copies of Axiom occupy almost no additional space (or
> time, since GIT will not rsync files that are duplicates).
> Surely Axiom will fit in a gig of disk space.
> 

"GIT only copies files when the checksums differ". Are you sure?
Are checksums that reliable? Can you give me a reference? But I
agree that GIT uses significantly less space than SVN (and Mercurial
uses even less). 

Regards,
Bill Page.

> -----Original Message-----
> From: Ben Collins-Sussman [mailto:address@hidden 
> Sent: October 9, 2006 2:14 PM
> To: address@hidden
> Cc: Gabriel Dos Reis; address@hidden
> Subject: Re: [Axiom-developer] RE: [M#73697383] Re: Disk-quota Request
> 
> 
> On 10/6/06, address@hidden
> <address@hidden> wrote:
> > Gabriel Dos Reis wrote:
> > > ...
> > > Can we get the 1G and be done with it?
> > >
> >
> > .. but then how would help debug the Google, svnsync, svk, and svn
> > programs? ;)
> >
> 
> Enough is enough.  You guys have been more than patient as 
> our guinea pigs!
> 
> I just rsync'd your sourceforge svn repository down to my local box
> (165MB), made a dumpfile from that, then did an 'svnadmin load' in our
> datacenter.  Disturbingly, it still took two hours to load the history
> and used up 381MB of space.  I don't know whether our size-counting
> code is buggy, or if our Bigtable storage schema is just really that
> bad, I'll be investigating.  It's not your problem.  :-)
> 
> You're now live... all 176 revisions are up and happy.  You're only
> using 381 of 750MB of quota, so you should be fine for a good while.
> 
> Let me know if you have any more problems.
> 
> (Remember, do an https:// checkout if you intend to commit changes;
> http:// checkouts produce read-only working copies.)
> 
>