Re: extensible metadata patch

[Colin Walters <walters verbum org>]

On Mon, 2013-09-09 at 16:05 +0100, Vivek Dasmohapatra wrote:
> > Let me know what you think!
>
> As long as I can stuff the sizes data in there (has to be a pair of
> size values for each checksummed object for my purposes, but I think
> you knew that), I'm good  with it.

Ok.  I'll go with the patch as is now since I think it's incrementally
better.

I have some more ideas going around though...for example, I wonder how
expensive it'd be to offer an option for "packed" commmits, where they
come with all metadata (plus your sizes information).

While this would increase the cost of the initial download of a commit
before we can even show them whether or not there's an OS upgrade, if
they do choose to take it, it'd be a lot more efficient than fetching
all of the individual metadata objects.

> With regards to your earlier comment about commits, I think we can combine the 
> two approches: If we can harvest the commit size data as we do the commit,
> for efficiency, as I do now, we can then use that cache as we traverse the 
> commit so we only have to load filez objects to get the sizes out if we
> dont have a cached value.
>
> Has the advantage of being fast and simple when it can be but correct
> for all cases, and won't normally trigger loading of all the filez objects
> into memory.

Ok, sounds good!