Linux

per day (2007-2008): (YT)

• 4.3k Lines added
• 1.8k Lines removed
• 1.5k Lines modified

And that change is proportional across all kernel parts:

• 50-55% of Kernel code is drivers
• 5% is core kernel

per day (2015): (YT)

• 10.8k Lines added
• 5.3k lines removed
• 1.9k lines modified

https://youtu.be/L2SED6sewRw?si=xr2RwLyOMzrMcAjm&t=864 There is no test in the traditional/popular sense of test.

Kernel is tested by running it.

Developers test it. Because there are hundreds of permutations of configs and conditions to test.

Zero day test (https://youtu.be/vyenmLqJQjs?si=leZ1mJ60eKRJXkjA&t=1493)

• Intel has 0-day bots that build the public linux kernel trees on different configurations and test a bunch of things