Re: New features in gitk

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Nov 1, 2007, 15:47 UTC
Message-ID: <alpine.LFD.0.999.0711010844260.3342@woody.linux-foundation.org>
In-Reply-To: <18217.47744.621850.100789@cargo.ozlabs.ibm.com>

On Thu, 1 Nov 2007, Paul Mackerras wrote:

Show 9 quoted lines

>
> Linus Torvalds writes: 
> > The cost is not generally in outputting the commits. The real cost is in 
> > traversing them in the first place. 
> 
> Actually, the biggest cost is still gitk reading in the commits from
> git log and doing the processing that gitk needs to do on each commit
> (which I have tried to minimize, and is way smaller than it used to
> be, but is still significant).

Umm. I think you're basing all your timings on hot-cache numbers.

The hot-cache numbers are already pretty damn good. But try this:

	echo 3 > /proc/sys/vm/drop_caches
	gitk

on a big repository, _especially_ one that isn't totally packed, or on a machine with a slow laptop disk. Just following the commit history is really quite expensive.

THAT is the problem with --topo-order.

			Linus