Shmmni, Shmseg, Shmmax : How To Know The Current Value On Solaris ? I would like to know the current value, how to read the value currentl

	Shmmni, Shmseg, Shmmax : How To Know The Current Value On Solaris ? - I would like to know the current value, how to read the value currentl
	Discussion by yordan with 6 Replies. Last Update: January 12, 2009, 7:49 pm

yordan

I have problems when installing Oracle on Solaris. The database files are correctly copied, but the instance does not startup, in the alert file I have a message saying that the the shm parameters are not correct.
How is it possible to know the current value of SHMMNI, SHMSEG, SHMMAX etc..., really reading them from the solaris kernel ?
I inserted some values in /etc/system, but how to know if these new values have been taken into account ?
The Oracle documentation says "ask the system administrator". Unfortunately, I am currently the solaris sytem administrator !

Thu Aug 24, 2006 Reply New Discussion

xboxrulz

Unfortunately, barely anyone here at Astahost use Solaris. The best bet is to go to the opensolaris.org website.

xboxrulz

Wed Jun 6, 2007 Reply New Discussion

yordan

QUOTE (xboxrulz)

Unfortunately, barely anyone here at Astahost use Solaris. The best bet is to go to the opensolaris.org website.

xboxrulz
Link: view Post: 104701

Thanks, I will try this way, or I will simply forget about it.

Tue Jun 12, 2007 Reply New Discussion

FeedBacker

Replying to yordan

The comand you must use is sysdef. The sysdef command shows the system definition, that includes the semaphores defined in the system.

Best regards

-reply by Asier Larrabide

Mon May 12, 2008 Reply New Discussion

bmfloyd

QUOTE (yordan)

Yordan, at this time I'm pretty sure you solved your problem and you are now a good Solaris Sysadmin :mellow:

As a guest said, the command 'sysdef' will tell you what you're looking for. Using it in conjuction with 'grep' it's very useful. For example: 'sysdef | grep SHMMNI' will tell you the current value for Shared Memory Identifiers.

Now, as you must know, these values are on the file '/etc/system' and it's VERY important before modifying this critical file to make a copy: 'cp -p /etc/system /etc/system.orig'. This way you can go back anytime if changes were disruptive and your system isn't booting properly. You can boot on Admin mode (init 1), and undo any change on '/etc/system' file.

Hope this helps somebody.

Sat Jan 10, 2009 Reply New Discussion

yordan

Thanks a lot.
Next time I go back to solaris (probably next month) I will remember "sysdef |grep -i shmseg".
Of course, my problem was very urgent, and I worked with probably false values (Oracle documentation says "change this value if it's smaller than xxx", and at this moment I had no idea if the value was smaller than yyy).

Sat Jan 10, 2009 Reply New Discussion

bmfloyd

QUOTE (yordan)

Let me know if you have a problem. Right now got a machine (sparc) working with Oracle 9.2 with next parameters:
set shmsys:shminfo_shmmax=2147483648
set shmsys:shminfo_shmmin=1
set shmsys:shminfo_shmmni=100
set shmsys:shminfo_shmseg=10

And another one with 10.2:
set shmsys:shminfo_shmmax=4294967295
set shmsys:shminfo_shmmin=1
set shmsys:shminfo_shmmni=1024
set shmsys:shminfo_shmseg=1024

As you can see, the second machine defers a lot from the first one, but both are working properly while met requirements of the Oracle RDBMS version.

Good luck.

Mon Jan 12, 2009 Reply New Discussion