If you've ever been running a program that requires a lot of CPU or hits the disk heavily, and then wanted to be able to use your computer for something else for a few minutes, this is the hint for you.
Most UNIX people know they can use Control-Z and the bg and fg commands to control whether or not their programs are running. What many often don't know is that you can do the same thing using signals. For instance, let's say I am doing a long build in Project Builder, but I need to use my computer for a few minutes at full speed to do something else. Here's how to accomplish that:
/Users/sam:> ps auxwww | grep Project sam 814 0.0 0.6 114984 5900 ?? S 4:24PM 0:01.56 /Developer/Applications/Project Builder.app/ Contents/MacOS/Project Builder -psn_0_5636097Here the id is 814 (line breaks were added above for narrower display width).
/Users/sam:> kill -SIGSTOP 814The program will now stop doing whatever it was doing and you can then do a quick render or whatever it was that needed the whole machine.
/Users/sam:> kill -SIGCONT 814It's as easy as that. I'm sure some enterprising individual could make a graphical program that does this for you, but I'm a UNIX user at heart.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20030915193440334