git version statistics

Just for fun, I've assembled a few statistics on git client versions that hit github.com. These are collected from the http user-agent strings provided by smart-http requests (we don't allow dumb http at all these days, and the git protocol does not provide any version information). It includes only the git/* entries (which are the vast majority of clients hitting "info/refs?service=.*"; the second biggest is JGit/*). And I counted each version only a single time from each IP (so this would skew if you had a lot of clients behind a single IP; their version would be counted only once).

Here are the results from the last few days:

  git/1.7.11.x |  0.1%   (0%) | 
  git/1.7.10.x | 21.1%  (21%) | **********************************
  git/1.7.9.x  | 11.4%  (32%) | ******************
  git/1.7.8.x  | 24.1%  (56%) | ****************************************
  git/1.7.7.x  | 12.2%  (68%) | ********************
  git/1.7.6.x  |  1.8%  (70%) | **
  git/1.7.5.x  |  8.2%  (78%) | *************
  git/1.7.4.x  |  7.2%  (86%) | ***********
  git/1.7.3.x  |  1.9%  (87%) | ***
  git/1.7.2.x  |  3.0%  (90%) | ****
  git/1.7.1.x  |  2.1%  (93%) | ***
  git/1.7.0.x  |  7.0%  (99%) | ***********
  git/1.6.6.x  |  0.0% (100%) | 

In this table, I've collapsed all of the x.y.z.* versions into a single string to get an overview (a more detailed table is below). The first percentage is the portion of the total requests; the second is a cumulative portion (so, for example, 90% of clients are running v1.7.2.x or higher, though only 3% are running v1.7.2.x itself).

Note that these numbers are skewed away from git versions lower than v1.6.6, because that is when we added smart http support. Requests over git:// or ssh are not included at all in these results.

For comparison, here's the same table from mid-September of 2011 (v1.7.7 was in -rc1 at the time):

  git/1.7.7.x |  0.2%   (0%) | 
  git/1.7.6.x | 19.3%  (19%) | *****************
  git/1.7.5.x |  8.0%  (27%) | *******
  git/1.7.4.x | 43.8%  (71%) | ****************************************
  git/1.7.3.x | 10.7%  (82%) | *********
  git/1.7.2.x |  4.9%  (86%) | ****
  git/1.7.1.x |  4.7%  (91%) | ****
  git/1.7.0.x |  8.2%  (99%) | *******
  git/1.6.6.x |  0.1% (100%) | 

So it seems that a large proportion of git users (or at least github users) stay within a few versions of the most current. In both cases, 70% are within 4 major releases of the most recent version.

Here's a more detailed table (from recent data), showing individual w.x.y.z versions:

  git/1.7.10.3 |  3.6%   (3%) | *******
  git/1.7.10.2 |  4.4%   (8%) | *********
  git/1.7.10.1 |  1.5%   (9%) | ***
  git/1.7.10   |  2.4%  (11%) | *****
  git/1.7.9.6  |  0.2%  (12%) | 
  git/1.7.9.5  |  9.2%  (21%) | *******************
  git/1.7.9.4  |  1.2%  (22%) | **
  git/1.7.9.3  |  0.3%  (22%) | 
  git/1.7.9.2  |  0.4%  (23%) | 
  git/1.7.9.1  |  0.4%  (23%) | 
  git/1.7.9    |  1.1%  (24%) | **
  git/1.7.8.6  |  0.3%  (25%) | 
  git/1.7.8.5  |  0.0%  (25%) | 
  git/1.7.8.4  |  0.7%  (25%) | *
  git/1.7.8.3  | 12.2%  (38%) | *************************
  git/1.7.8.2  | 18.8%  (56%) | ****************************************
  git/1.7.8.1  |  0.1%  (56%) | 
  git/1.7.8    |  0.3%  (57%) | 
  git/1.7.7.6  |  0.5%  (57%) | *
  git/1.7.7.4  |  0.2%  (57%) | 
  git/1.7.7.3  |  0.4%  (58%) | 
  git/1.7.7.2  |  0.1%  (58%) | 
  git/1.7.7.1  |  0.0%  (58%) | 
  git/1.7.7    |  0.7%  (59%) | *
  git/1.7.6.5  |  0.1%  (59%) | 
  git/1.7.6.4  |  0.2%  (59%) | 
  git/1.7.6.3  |  0.0%  (59%) | 
  git/1.7.6.1  |  0.5%  (59%) | *
  git/1.7.6    |  0.7%  (60%) | *
  git/1.7.5.4  | 10.9%  (71%) | ***********************
  git/1.7.5.3  |  0.1%  (71%) | 
  git/1.7.5.2  |  0.1%  (71%) | 
  git/1.7.5.1  |  0.2%  (71%) | 
  git/1.7.5    |  0.1%  (71%) | 
  git/1.7.4.5  |  0.4%  (72%) | 
  git/1.7.4.4  |  3.3%  (75%) | *******
  git/1.7.4.3  |  0.0%  (75%) | 
  git/1.7.4.2  |  0.0%  (75%) | 
  git/1.7.4.1  |  5.3%  (81%) | ***********
  git/1.7.4    |  0.2%  (81%) | 
  git/1.7.3.5  |  0.2%  (81%) | 
  git/1.7.3.4  |  1.2%  (82%) | **
  git/1.7.3.3  |  0.1%  (82%) | 
  git/1.7.3.2  |  0.4%  (83%) | 
  git/1.7.3.1  |  0.1%  (83%) | 
  git/1.7.3    |  0.1%  (83%) | 
  git/1.7.2.5  |  3.6%  (86%) | *******
  git/1.7.2.3  |  0.3%  (87%) | 
  git/1.7.2.2  |  0.1%  (87%) | 
  git/1.7.2.1  |  0.0%  (87%) | 
  git/1.7.2    |  0.1%  (87%) | 
  git/1.7.1.1  |  0.1%  (87%) | 
  git/1.7.1    |  2.8%  (90%) | ******
  git/1.7.0.6  |  0.0%  (90%) | 
  git/1.7.0.5  |  0.0%  (90%) | 
  git/1.7.0.4  |  7.0%  (97%) | **************
  git/1.7.0    |  2.6%  (99%) | *****
  git/1.6.6    |  0.0% (100%) | 

The interesting thing to me is how spiky it is, and where the spikes fall. I would expect to see a spike around the highest maint release of each major version (so v1.7.8.6, for example, with many fewer installs of v1.7.8.5, v1.7.8.4, and so forth). But that's not what happens. The most popular v1.7.8.x versions are .3 and .2, and hardly anybody bothered to move to v1.7.8.6.

I can only assume these are skewed by some widely-used binary distribution being locked onto particular versions (e.g., the spike at v1.7.2.5 represents Debian stable).

If anybody has suggestions for other interesting analyses to perform, let me know.

-Peff