Heh, 10 years old, original link doesn't work, image is tiny. And it sounds like they were comparing Linux and Apache to IIS and Windows.
It's hard to evaluate this in any way more than "yeah that's a cute spaghetti diagram". If I wanted to drag Linux through the mud visually I'd depict how much time every socket I/O op spends in vfs/fsync stuff. (i.e. you can depict anything to make your point)
That might be a cool diagram to show! I honestly know nothing about kernel programming, just happened to come across that a long time ago and bookmarked it.
The second image is of IIS running on Windows, not Apache. Different software on different OSes. Regardless, it doesn't seem like parent is making the argument that the NT kernel isn't complicated - just that it is superior.
It is more complicated because -- surprise -- I/O usage patterns do not fit in one neat little box, and you have to provide special handling of special cases that do occur frequently in the real world.
It's hard to evaluate this in any way more than "yeah that's a cute spaghetti diagram". If I wanted to drag Linux through the mud visually I'd depict how much time every socket I/O op spends in vfs/fsync stuff. (i.e. you can depict anything to make your point)