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Top Forums UNIX for Dummies Questions & Answers Semaphores
# 1  
Old 01-28-2002

Hi all,

I am using HP 10.20 on A 9000/785. My question is:

If I am the only person logged in as root at the moment, how many "semaphore proccesses" should I have?? Is it only one, or it is relevant to other system proccesses?

Here is what I get listing the current semaphores

# ipcs -sp
IPC status from /dev/kmem as of Mon Jan 28 11:52:28 2002
s 0 0x2f180002 --ra-ra-ra- root sys
s 1 0x411c02e1 --ra-ra-ra- root root
s 2 0x4e0c0002 --ra-ra-ra- root root
s 3 0x412001f9 --ra-ra-ra- root root
s 4 0x00446f6e --ra-r--r-- root root
s 5 0x00446f6d --ra-r--r-- root root
s 6 0x01090522 --ra-r--r-- root root
s 7 0x0000002a --ra------- root root
s 72 0x4c1c30ab --ra-r--r-- daemon daemon
s 9 0xeb06e52e --ra------- root root

I killed a couple of semaphores from previous users, but right now I am the only user logged in (root). Would it be OK to kill some semaphores that are unsed and how do I identified these?
Thanks alot
# 2  
Old 01-28-2002
You should be very careful about killing processes if you don't know what they are used for.
On the other hand, if you don't mind crashing your system, it is an excellent way to learn!

There will be semaphores for other processes that are running as root. Just because you are the only one logged in, the system has processes running to keep the system up (swapper, init, statdaemon, supsched) and running. Killing one of these would help insure your name would be know to all in your company. Look at the ID column in the output, do a ps -ef and grep for each ID. You will see what the semaphores are being used for.

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