RPI3 swap experiments, was Re: GPT vs MBR for swap devices

[bob prohaska]

I've tried to replicate  the RPi3  "run out of swap" experiment after
updating source, kernel and world to r335576. Roughly the same things happen:
Errors flood the console, when swap usage goes a bit over 80% the machine becomes
unresponsive.  No sign of the OOM assassin. 

However, -j4 buildworld got all the way to building libraries. With r334939 it
always stopped in cross tools. That seems like a significant improvement
in swap usage efficiency. Is this to be expected? 

What details were captured can be seen at
http://www.zefox.net/~fbsd/rpi3/swaptests/r335576/1gbsdflash/
in case they're of interest.

Thanks for reading,

bob prohaska