Why rsync are always interrupted?

rsync error: received SIGUSR1 (code 19) at main.c(1285)

Double Cores with io wait 100%, mean what?

Why sdc sdd write usage so high, so busy? It just write 1Mbps network data to write only!

What is the relationship between load and cpu ?

http://askubuntu.com/questions/9487/whats-the-difference-between-load-average-and-cpu-load

http://www.linuxjournal.com/article/9001

Why load is high, but cpu percentage is low?

http://blog.scoutapp.com/articles/2009/07/31/understanding-load-averages // Good example using car traffic