Re: Mercurial 0.3 vs git benchmarks

From: Bill Davidsen
Date: Tue Apr 26 2005 - 11:23:41 EST


Linus Torvalds wrote:

On Mon, 25 Apr 2005, Mike Taht wrote:

One difference is probably - mercurial appears to be using zlib's *default* compression of 6....

using zlib compression of 9 really impacts git...


I agree that it will hurt for big changes, but since I really do believe that most changes are just a couple of files, I don't believe it matters for those.

I forget what the exact numbers were, but I did some timings on plain
"gzip", and it basically said that doing gzip on a medium-sized file was
not that different for -6 and -9. Why? Because most of the overhead was
elsewhere ;)

Certainly not different in the overall numbers, but after trying gzip on a bunch of various source files on 32 bit CPUs, from P-II to Xeon, it looks as if after 7 the cpu jumps about 40% to 8, and another 30% to 9. Neither 8 nor 9 give any significant size improvement (< 2%).

Again, this is 32 bit CPU and just the gzip component, reading from stdin and writing to stdout which I hope gets directory operations out of the time measure.

Sample attached.

--
-bill davidsen (davidsen@xxxxxxx)
"The secret to procrastination is to put things off until the
last possible moment - but no longer" -me
Comp level 1

real 0m1.972s
user 0m1.790s
sys 0m0.098s
-rw-r--r-- 1 davidsen 1792050 Apr 26 11:56 dummy.tar.gz
Comp level 2

real 0m2.021s
user 0m1.858s
sys 0m0.097s
-rw-r--r-- 1 davidsen 1737227 Apr 26 11:56 dummy.tar.gz
Comp level 3

real 0m2.296s
user 0m2.124s
sys 0m0.095s
-rw-r--r-- 1 davidsen 1697644 Apr 26 11:56 dummy.tar.gz
Comp level 4

real 0m2.604s
user 0m2.423s
sys 0m0.099s
-rw-r--r-- 1 davidsen 1593207 Apr 26 11:56 dummy.tar.gz
Comp level 5

real 0m3.181s
user 0m3.003s
sys 0m0.087s
-rw-r--r-- 1 davidsen 1549050 Apr 26 11:56 dummy.tar.gz
Comp level 6

real 0m4.185s
user 0m3.965s
sys 0m0.089s
-rw-r--r-- 1 davidsen 1531866 Apr 26 11:56 dummy.tar.gz
Comp level 7

real 0m4.889s
user 0m4.642s
sys 0m0.096s
-rw-r--r-- 1 davidsen 1524350 Apr 26 11:57 dummy.tar.gz
Comp level 8

real 0m7.836s
user 0m7.532s
sys 0m0.085s
-rw-r--r-- 1 davidsen 1513763 Apr 26 11:57 dummy.tar.gz
Comp level 9

real 0m11.020s
user 0m10.616s
sys 0m0.092s
-rw-r--r-- 1 davidsen 1511970 Apr 26 11:57 dummy.tar.gz