Re: Mercurial 0.3 vs git benchmarks

Linus Torvalds
2005-04-26T02:06:43Z

On Mon, 25 Apr 2005, Matt Mackall wrote:
>
> Here are the results of checking in the first 12 releases of Linux 2.6
> into empty repositories for Mercurial v0.3 (hg) and git-pasky-0.7.
> This is on my 512M Pentium M laptop. Times are in seconds.
>
> user system real du -sh
> ver files hg git hg git hg git hg git
>
> 2.6.0 15007 19.949 35.526 3.171 2.264 25.138 87.994 145M 89M
> 2.6.1 998 5.906 4.018 0.573 0.464 10.267 5.937 146M 99M
> 2.6.2 2370 9.696 13.051 0.752 0.652 12.970 15.167 150M 117M
> 2.6.3 1906 10.528 11.509 0.816 0.639 18.406 14.318 152M 135M
> 2.6.4 3185 11.140 7.380 0.997 0.731 15.265 12.412 156M 158M
> 2.6.5 2261 10.961 6.939 0.843 0.640 20.564 8.522 158M 177M
> 2.6.6 2642 11.803 10.043 0.870 0.678 22.360 11.515 162M 197M
> 2.6.7 3772 18.411 15.243 1.189 0.915 32.397 21.498 165M 227M
> 2.6.8 4604 20.922 16.054 1.406 1.041 39.622 25.056 172M 262M
> 2.6.9 4712 19.306 12.145 1.421 1.102 35.663 24.958 179M 297M
> 2.6.10 5384 23.022 18.154 1.393 1.182 40.947 32.085 186M 338M
> 2.6.11 5662 27.211 19.138 1.791 1.253 42.605 31.902 193M 379M

That time in checking things in is worrisome.

"git" is basically linear in the size of the patch, which is what I want,
since most patches I work with are a couple of files at most. The patches
you are checking in are huge - I never actually work with a change that is
as big as a whole release. I work with changes that are five files or
something.

"hg" seems to basically slow down the more patches you have applied. It's
hard to tell from the limited test set, but look at "user" time. It seems
to increase from 6 seconds to 27 seconds.

To make an interesting benchmark, try applying the first 200 patches in
the current git kernel archive. Can you do them three per second? THAT is
the thing you should optimize for, not checking in huge changes.

If you're checking in a change to 1000+ files, you're doing something
wrong.

> Full-tree working dir diff (2.6.0 base with 2.6.1 in working dir):
> hg: real 4.920s user 4.629s sys 0.260s
> git: real 3.531s user 1.869s sys 0.862s
> (this needed an update-cache --refresh on top of git commit, which
> took another: real 2m52.764s user 2.833s sys 1.008s)

You're doing something wrong with git here. Why would you need to update
your cache?

Linus