Re: [RFC] Faster git grep.

From: Jeff King <peff@peff.net>
Date: Jul 25, 2013, 20:08 UTC
Message-ID: <20130725200857.GB1225@sigill.intra.peff.net>
In-Reply-To: <20130725182905.GA7664@domone.kolej.mff.cuni.cz>

On Thu, Jul 25, 2013 at 08:29:05PM +0200, Ondřej Bílka wrote:

> One solution would be to use same trick as was done in google code.
> Build and keep database of trigraphs and which files contain how many of
> them. When querry is made then check
> only these files that have appropriate combination of trigraphs.

That seems like a sensible approach.

> Updating database would be relatively inexpensive compared to disk
> access we need to do anyway.

Yes, I think it can be quite cheap, since you would only need to re-index files that have changed (and git is very quick at telling you what those files are).

> A space usage might be problem so which is why I decided go option
> route.
> 
> Comments, pointers?

I think it is a good idea, but not need to be part of core git. It seems more like you would want to glue together an existing code-indexing solution (like codesearch) with git (which would provide the list of files to index and to search).

If that proves useful in practice, but the interface is clunky for whatever reason, then a good follow-on project could be to build support for updating and using the index via the usual "git grep".

-Peff