Subject: Re: how to speed up "git log"?

From: Bruno Haible <[email-masked]>
Date: Mon, 12 Feb 2007 00:41:27 +0100

Hello Johannes,

Thanks for the helpful answer.

> Yes, because there were only 147 commits which changed the file. But git 
> looked at all commits to find that.

Ouch.

> Basically, we don't do file versions. File versions do not make sense, 
> since they strip away the context.

Is there some other concept or command that git offers? I'm in the situation
where I know that 'tr' in coreutils version 5.2.1 had a certain bug and
version 6.4 does not have the bug, and I want to review all commits that
are relevant to this. I know that the only changes in tr.c are relevant
for this, and I'm interested in a display of the minimum amount of relevant
commit messages. If "git log" is not the right command for this question,
which command is it?

> > 2) Why so much system CPU time, but only on MacOS X?
> 
> Probably the mmap() problem. Does it go away when you use git 1.5.0-rc4?

No, it became even worse: git-1.5.0-rc4 is twice as slow as git-1.4.4 for
this command:
  git-1.4.4: 25 seconds real time, 24 seconds of CPU time (12 user, 12 system)
  git-1.5.0: 50 seconds real time, 39 seconds of CPU time (20 user, 19 system)

Bruno