Re: [RFD/PATCH] Implement pack.compression and pack-objects --compression=N

[Nicolas Pitre <nico@cam.org>]

On Thu, 3 May 2007, Junio C Hamano wrote:

> "Dana How" <danahow@gmail.com> writes:
> 
> > So for a 25% increase in blob size I get 33% less elapsed time
> > in git-add, all by changing core.compression from -1 to 1.
> > I'll definitely take that improvement.  [For the compressible files
> > we typically have, using 0 is a bad idea:  the CPU "advantage"
> > is swamped out by the time to write a much larger file.]
> 
> The above number is about loose objects, right?
> 
> > Since I don't care [to the same degree] about the responsiveness of
> > packing,  I'd rather pack with -1 or better to keep packs small.
> 
> I see.  You are saying that the fact that core.compression is
> used also for packing makes the variable less useful.

I think that would make sense to have separate configs for pack and 
loose object compression.  When not specified they should simply default 
to core.compression if it exists.  Otherwise I'd suggest that pack 
compression default level be Z_DEFAULT_COMPRESSION and loose object 
compression default level be Z_BEST_SPEED.  This would make interactive 
operations like git-add and git-commit even faster by default.


Nicolas