Re: [PATCH v1] diffcore-rename: speed up register_rename_src
- Date: Tue, 18 Apr 2017 21:32:15 -0400
- From: Jeff King <peff@xxxxxxxx>
- Subject: Re: [PATCH v1] diffcore-rename: speed up register_rename_src
On Tue, Apr 18, 2017 at 07:44:21PM +0000, git@xxxxxxxxxxxxxxxxx wrote:
> From: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
> Teach register_rename_src() to see if new file pair
> can simply be appended to the rename_src array before
> performing the binary search to find the proper insertion
I guess your perf results show some minor improvement. But I suspect
this is because your synthetic repo does not resemble the real world
very much. You're saving a few strcmps, but for each of those files
you're potentially going to have actually zlib inflate the object
contents and do similarity analysis.
So "absurd number of files doing 100% exact renames" is the absolute
best case, and it saves a few percent.
I dunno. It is not that much code _here_, but I'm not excited about the
prospect of sprinkling this same "check the last one" optimization all
over the code base. I wonder if there's some way to generalize it.