topic Re: Cannot Access Semaphore Identifier in Operating System - HP-UX

Cannot Access Semaphore Identifier

TMcB — Mon, 13 Dec 2004 08:59:24 GMT

We have a problem on our HPUX 11.00 server running Informix Database.
The /usr2 directory has been filling up to 100%.

This is because a log file called MSGRCV fills up with the following messages :
ERROR: cxmm600a: error occurred
message error = Cannot Set Semaphore for Exclusive Shared Memory Access (9)
system error = Identifier removed (36)
ERROR: cxmm600a: error occurred
message error = Cannot Access Semaphore Identifier (8)
system error = No such file or directory (2)

I don't really know where to start looking - does anyone have any ideas what could be causing this

Much appreciated.

Re: Cannot Access Semaphore Identifier

Steven E. Protter — Mon, 13 Dec 2004 09:14:02 GMT

What is the /usr2 used for.

What to do depends on use.

It would appear you may not have enough shared memroy.

With glance gpm you can check shared memory use. If you are close to 100% consider increaseing it.

shmmax
shmseg
shmmni

With 11.00 you must set and compile a new kernel.

SEP

Re: Cannot Access Semaphore Identifier

TMcB — Mon, 13 Dec 2004 09:26:11 GMT

Thanks for the reply.
What should I be looking at in glance?

The kernel params are set as follows :
Shmmax 536870912
shmseg 512
shmmni 768

IPCS shows the following :
IPC status from /dev/kmem as of Mon Dec 13 14:22:38 2004
T ID KEY MODE OWNER GROUP
Shared Memory:
m 0 0x411c04c2 --rw-rw-rw- root root
m 1 0x4e0c0002 --rw-rw-rw- root root
m 2 0x412002ae --rw-rw-rw- root root
m 7683 0x0c6629c9 --rw-r----- root root
m 4 0x06347849 --rw-rw-rw- root root
m 3077 0x52574801 --rw-rw---- root informix
m 54534 0x52574802 --rw-rw-rw- root informix
m 1543 0x00000000 D-rw-rw-rw- fmd_prod sgmfmd
m 35336 0x00000000 D-rw-rw-rw- fmd_prod sgmfmd
m 3849 0x00000000 D-rw-rw-rw- fmd_prod sgmfmd
m 3082 0x00000000 D-rw-rw-rw- fmd_prod sgmfmd
m 3083 0x00000000 D-rw-rw-rw- fmd_prod sgmfmd
m 3084 0x00000000 D-rw-rw-rw- fmd_prod sgmfmd
m 5389 0x00000012 --rw-rw-rw- fmd_prod sgmfmd
m 8462 0xffffffff --rw-r--rw- root sys
m 6173 0x00000000 D-rw-rw-rw- fmd_prod sgmfmd

Re: Cannot Access Semaphore Identifier

Steven E. Protter — Mon, 13 Dec 2004 09:29:33 GMT

X Windows:

gpm
reports
system tables report

Shared memory usage is all over this report.

gpm/glance is a pay for add in product but it can be installed of the Core OS or application cd's for a 60 day fully functional trial.

SEP

Re: Cannot Access Semaphore Identifier

TMcB — Mon, 13 Dec 2004 09:40:25 GMT

Below is the info from glance :

system table Avail Used Util% High%
proc table 1620 177 11% 11%
file table 6419 1290 38% 38%
shared mem 768 16 2% 2%
message table 255 11 4% 4%
semaphore 766 24 3% 3%
file locks 800 41 5% 5%
pseudo term 100 1 1% 1%
buffer head 68380 na na

system table Avail Reqs Used High
shared mem 384gb 168gb
message buf 223mb 0 0
inode cache 2668 1083 1776
DNLC cache 3692

Min Max Avail Used High
buffer cache 89mb 358mb 358mb 358mb na

Re: Cannot Access Semaphore Identifier

Stephen Keane — Mon, 13 Dec 2004 10:59:09 GMT

msgrcv is a message queue log file, not a shared memory/semaphore log file. The semaphore might be being used to control access to the message queue. The output of ipcs is probably not going to help as the message queue in question is probably no longer there.