Re: [PATCH 2/3] gitweb: Cache $parent_commit info in git_blame()

[Luben Tuikov <ltuikov@yahoo.com>]

--- On Wed, 12/10/08, Jakub Narebski <jnareb@gmail.com> wrote:
> > Have you tested this patch that it gives the same
> commit chain
> > as before it?
> 
> The only difference between precious version and this patch
> is that
> now, if you calculate sha-1 of $long_rev^, it is stored in 
> $metainfo{$long_rev}{'parent'} and not calculated
> second time.

Yes, I agree a patch to this effect would improve performance
proportionally to the history of the lines of a file.  So it's a
good thing, as most commits change a contiguous block of size more
than one line of a file.

"$parent_commit" depends on "$full_rev^" which depends on "$full_rev".
So as soon as "$full_rev" != "$old_full_rev", you'd know that you need
to update "$parent_commit".  "$old_full_rev" needs to exist outside the
scope of "while (1)".  I didn't see this in the code or in the patch.

> But I have checked that (at least for single example file)
> the blame output is identical for before and after this patch.

I've always tested it on something like "gitweb.perl", etc.

    Luben