Weird Application Freezes
I've noticed lately that on occasions, an OS X programs tend to spontaneously freeze, with no way to kill the process except to do a reboot.
This is what happens:
I'll perform some action, and I'll get the spinning beach ball. The System Monitor tells me that the process is not responding. If I do a "Force Quit", which won't do anything. I'll open up iTerm and try a kill -9 on the process. This doesn't work either. Instead, I see another process (with what I think is a different process ID) with the name of the application.
So if iTunes is the program that froze, I'll see something like this if I do a ps -ax:
300 ?? S (iTunes)
If iTunes is running normally, this is what I see:
300 ?? S 1:02.07 /Applications/iTunes.app/Contents/MacOS/iTunes -psn_0
No matter how many times I try to kill -9 that process with the name in parentheses, it won't die. What's more, the dock still shows the application open, with "Force Quit" in the context menu. The app is still frozen.
I have a revision A Intel iMac that I bought in March. I've installed all the system updates. This problem only started showing up in the last month or month in a half. It doesn't happen that frequently, but I see it once in a while.
From memory, this happened three times. These were the programs:
1) Quicksilver
2) iTunes
3) Mail.app
Has anybody else encountered this? What I'd like to better understand is why I can't kill the process. It should be possible to kill any runaway process on any Unix OS.
This is what happens:
I'll perform some action, and I'll get the spinning beach ball. The System Monitor tells me that the process is not responding. If I do a "Force Quit", which won't do anything. I'll open up iTerm and try a kill -9 on the process. This doesn't work either. Instead, I see another process (with what I think is a different process ID) with the name of the application.
So if iTunes is the program that froze, I'll see something like this if I do a ps -ax:
300 ?? S (iTunes)
If iTunes is running normally, this is what I see:
300 ?? S 1:02.07 /Applications/iTunes.app/Contents/MacOS/iTunes -psn_0
No matter how many times I try to kill -9 that process with the name in parentheses, it won't die. What's more, the dock still shows the application open, with "Force Quit" in the context menu. The app is still frozen.
I have a revision A Intel iMac that I bought in March. I've installed all the system updates. This problem only started showing up in the last month or month in a half. It doesn't happen that frequently, but I see it once in a while.
From memory, this happened three times. These were the programs:
1) Quicksilver
2) iTunes
3) Mail.app
Has anybody else encountered this? What I'd like to better understand is why I can't kill the process. It should be possible to kill any runaway process on any Unix OS.
Comments
What I'd like to better understand is why I can't kill the process. It should be possible to kill any runaway process on any Unix OS.
It should be possible but sometimes processes do stuff that is outside the kernel protection. These are mainly hardware processes like CD/DVD burning and things or even hard drive stuff.
The main apps I've had this kind of problem with are the Finder, Quicktime, Disk Utility and Toast. This is one reason I use an external burner because if anything does hang up, I can unplug it and it frees up the system.
I haven't experienced it in a while but it is certainly annoying when it happens because you expect that a unix OS gives the user control over everything.
I wish someone would produce a method of controlling hardware interactions or whatever it was that caused your hangs but I suspect performance may be at risk. One thing I hate most is being susceptible to a graphics driver hang. I've had that a few times and you pretty much have to restart because you can't see anything. If OS X detects that the driver is down, it should start it back up again.