Zombie
There are ways around that on a pc, but for an Android, I can not speak. You probably have more knowledge than I possess. I'm learning slowly in an attempt to resolve all of the nonsense I am experiencing with my phone.
You can enable the "Include phone processes" and "Display all phone
processes" options in preferences. Once slected, you'll see things
like kswapd, and all the other kernel threads. The IO and IRQ will be
accounted for in one of them. Normally, they're hidden since there
isn't really anything you can do with them, and they would cause more
confusion.
Enable those options, and when you're having a slowdown, launch
Watchdog and hit real-time. You'll find something that might be useful
for further searching.
Robert