Re: Terrible bad performance for it blame --date=iso -C -C master -- <file>

[Junio C Hamano <gitster@pobox.com>]

Samuel Lijin <sxlijin@gmail.com> writes:

> On Fri, Mar 31, 2017 at 10:52 AM, Junio C Hamano <gitster@pobox.com> wrote:
>
>> It might not be a bad idea to teach "blame" not to pay attention to
>> any path that is marked as "-diff" (e.g. binary files) when trying
>> to see if remaining contents appeared by borrowing from them.  We do
>> not have that heuristics (yet).
>
> Could you elaborate on this? Do you mean to tell diffcore-rename to
> ignore diff_filespec objects if they're binary?

No and yes ;-).  I do not think it is a good idea to unconditionally
ignore binary in diffcore-rename.

But when we know that the rename detection is called from inside
blame.c, where by definition we would be digging line-oriented
contents, there is no point checking if the contents we are looking
for came from an existing binary file.