We started collecting metrics in 2011. Reviewing the history you can see the growth and evolution of the community.
Measuring open source communities is very hard. The nature of being open and redistributable means that we definitely do not know everyone who is using it and that’s part of being open. These metrics can provide insight into trends within the community but should not be considered exhaustive or even close to complete but as a consistent snapshot. We have public instructions for setting up mirrors and these measurements do not count the any statistics for mirrors either private or public. Public mirrors are listed at http://wiki.ros.org/Mirrors
Every year we seek to provide the same metrics so that trends can be observed. However we also look to update the metrics to include new statistics or cover new aspects that we think may be interesting trends in the future. This year we haven’t updated any fields.
In this report the biggest thing that stood out to me was the growth of ROS Discourse. The delta on the number of users might be a little off due to estimations to correct the spam attack last year. But reviewing all the numbers there’s been a lot more activity overall on Discourse.
One outlier that I believe is not super representative is that the number of wiki pages dropped. Part of this is because when I was collecting the number I realized that we hadn’t run our periodic “trash” page cleanup. This is a technical term from the Moin Moin Tuning Guide and maintenance routines for pages that have metadata that’s created but no content. One of the things that Moin Moin does is that it creates pages if you browse to them by accident. So every 404 creates a “trash” page. When collecting the stats I noticed that we had way too many pages and ran the cleanup script which removed 14750 pages, otherwise it would look like we almost doubled the number of pages. This has not been run immediately preceding the stats collection in the past so it adds noise to the measurements based on how long from the last cleanup operation. In the future I’ll plan to run the cleanup before collecting stats.