The most surprising thing about today's year-end discussion is that the number of new commits to the Linux kernel this year hit a ten-year low. But it's not all bad, as the annual metric by row count is comparable to recent years.
As of this morning, running GitStats on the LinuxGit source tree revealed that there are 1,324,647 commits in the Git tree from about 29,380 different authors... The kernel has had 75,314 commits this year, compared to 87,993 last year and 86,790 the year before that.
Since 2017, annual submissions have typically been between 80,000 and 90,000, but this year they dropped to 75,000. Between 2014 and 2016, the number of submissions per year was about 70,000. At first I was thinking that maybe the alignment of the merge window/kernel release cadence with the calendar year plays a role, but when comparing the number of kernel releases per year it doesn't seem to, and the ten years of activity don't change.
But the number of submissions is only an indicator. This year, 3,694,098 lines of code were added and 1,490,601 lines of code were deleted. This is comparable to the situation in previous years. Last year, 3.3 million rows were added and 1.59 million rows were deleted... Although it is lower than the 5.3 million rows in 2022, the number of new rows in 2021 is also around 3.2 million. So, in terms of code activity, Linux kernel activity in 2024 will be roughly the same as in previous years, just with a lot fewer commits.
Linus Torvalds, who manages all merges into the mainline kernel while also making many of his own patches, still leads the list this year with 2877 commits... most of which are from merges. They are followed by KrzysztofKozlowski (Linaro), Jakub Kicinski (Meta), Kent Overstreet (Bcachefs), Arnd Bergmann (Linaro), and Andy Shevchenko (Intel) as the developers with the most commits this year.
In 2024, the number of Linux kernel authors will be approximately 4,807.
The number of lines in the Linux kernel source tree continues to grow, and it is expected that by 2025, the number of lines of code, documentation, and other contained text sources in the kernel tree will exceed 40 million lines.