Some random notes follow. This page is not intended to give advice as such, and probably contains trivia for the most part.

Init and related low-level processes

(This is on Ubuntu 10.04.)

Two processes without a parent as such:

% ps -ef | awk '$3==0 {print}'
root         1     0  0 Aug22 ?        00:00:00 /sbin/init
root         2     0  0 Aug22 ?        00:00:00 [kthreadd]

Consequently you could also do:

% ps -ef | awk '$3==2 {print}'

to list all kernel threads.

Hidden in plain sight

dd has one of the shortest man pages, yet I've obviously not read the end of it… :-)

Thanks to MeeGo.com for helping me see the light, here's how to get status on the progress of a dd process:

Sending a USR1 signal to a running ‘dd’ process makes it print I/O statistics to standard error and then resume copying.