From: Josef Weidendorfer <josef.weidendorfer@gmx.de>
Date: Wed, 13 Jun 2007 16:27:07 GMT
Subject: Re: That improved git-gui blame viewer..
Message-ID: <200706131827.08163.Josef.Weidendorfer@gmx.de>
In-Reply-To: <Pine.LNX.4.64.0706131553390.4059@racer.site>

On Wednesday 13 June 2007, Johannes Schindelin wrote:
> ~1.4s	log _with_ --pretty=raw
> ~3.5s	log _with_ --pretty=raw _and_ -z (!)

That happens on linux, too.

I am not really familiar with that code, but comparision
of the call graphs of "git log" vs. "git log -z", as
produced by callgrind (shameless plug) and visualized
by kcachegrind (again, another shameless plug) shows
that the difference happens in log_tree_diff, called
from log_tree_commit.

While without "-z", log_tree_diff immediatly returns
because "opt->diff" is 0, in the case of "-z",
the tree differences are fully done even not used at all ?!

The result is that "log_tree_commit" executes (inclusive
callees) 340 million instructions without "-z", while
it runs 2300 million instructions in the "-z" case.

Josef