LWN: Comments on "Some 4.12 development statistics"

Metrics

andy_shev — Tue, 01 Aug 2017 16:21:10 +0000

Probably I didn't put it clear, I meant independent "modules / drivers" under "files", and statistics here is "by changesets".

$ gt4tree.sh v4.12..origin/master
Christoph Hellwig (246):
Mauro Carvalho Chehab (169):
Thomas Gleixner (143):
Takashi Iwai (130):
Chris Wilson (126):
Arvind Yadav (122):
...

See the last name in the list, here. While I appreciate the work done by Arvind, it's still a mechanical routine which can be easily scripted (coccinelle, sed, etc).

Metrics

corbet — Mon, 31 Jul 2017 13:42:33 +0000

As far as I've been able to tell, the results that come out of cregit closely match the (simpler) "by lines" metric.

Metrics

pabs — Mon, 31 Jul 2017 02:55:19 +0000

Maybe something based on tokens using cregit?

Metrics

corbet — Sun, 30 Jul 2017 19:09:58 +0000

Nothing I've done here counts the number of affected files, so not necessarily. But I'll freely admit that the metrics used here — changesets and changed lines — are awful. I'd sure like to find something better if anybody has any good ideas.

Some 4.12 development statistics

andy_shev — Sun, 30 Jul 2017 15:31:32 +0000

I didn't check myself so the following question. Imagine that a maintainer does

% sed -i -e 's/old_api_call/new_api_call/g' <list of affected files>

If number of list of affected files greate than let's say 100 she or he immediatelly poped up in the statistics, right? But it's not what we would like to see there for my point of view.

Some 4.12 development statistics

corbet — Fri, 07 Jul 2017 16:25:32 +0000

Yes, that's a manual fix for $REASONS; it got done then undone when I fixed an unrelated problem. Fixed again.

Some 4.12 development statistics

kdave — Fri, 07 Jul 2017 15:12:56 +0000

'Novell' as an employer does not exist anymore, s/Novell/SUSE/.

Some 4.12 development statistics

broonie — Thu, 06 Jul 2017 19:19:30 +0000

It's common to get very big line counts by doing things like removing old drivers or adding new devices with large register sets where you can often get big machine generated sets of register definitions and/or defaults.

Some 4.12 development statistics

dankohn — Wed, 05 Jul 2017 18:10:46 +0000

For posterity, Jon Corbet responded to me by email to explain:

In short, to get the numbers for (say) Intel, I do a normal-looking gitdm
run but add:

-C "Intel" -f intel.files

That will (1) only look at commits from an Intel employee, and (2) put a
list of touched files in "intel.files". A "sort -rn" on that file will
put them into decreasing order, at which point the numbers are relatively
easy to pick out.

Some 4.12 development statistics

arnd — Wed, 05 Jul 2017 09:32:53 +0000

I made a chart showing the git trees that contributed most to the kernel over time, by number of patches and number of lines:

https://docs.google.com/spreadsheets/d/15lFZZ_RygzGgwJSPc...

In 4.12 both staging and drm were really big compared to the rest. We have had previous releases in which one of them dominated the total patch count or diff size but not both at the same time, and we have other trees that are relatively big (net-next, tip, arm-soc, ...) but more constant.

Some 4.12 development statistics

gby — Wed, 05 Jul 2017 07:11:59 +0000

They most probably didn't *really* read many of those lines and almost for sure did not author many of them. For example, most of the 17,593 lines listed under my name were written by others. I'm just the one upstreaming the driver and maintaining it. Tons of that code tends to be a long include file full of register and descriptor definitions, quite often auto-generated from hardware definition files.

Some 4.12 development statistics

dgm — Wed, 05 Jul 2017 06:24:17 +0000

I find it astonishing that Alex Deucher and Alan Cox have handled to touch more than half a million lines of code between them two. I'm not sure if I would be able to *read* that many lines, much less change them.

Some 4.12 development statistics

pabs — Wed, 05 Jul 2017 05:48:27 +0000

This is definitely the first time I've seen it on LWN.

Some 4.12 development statistics

dankohn — Tue, 04 Jul 2017 19:52:35 +0000

Is the directory per company info a new feature? Could you please say how to generate it from gitdm?