Folks -
Here is my understanding of this. I don't work on ovwdb but the cache
size is the first thing Support checks when things seem to be working
slowly or funny.
We don't recommend that you use zero for the ovwdb cache size. Yes, it
will auto-adjust but that will result in slower initialization and
possibly slower running as well. We have seen this in the performance
lab. Here's the explanation I was given.
When the cache size is 0, ovwdb starts out with a default value for the
size, usually much smaller than what any typical network needs, and when
he runs out of memory to store the database in, then he allocates another
chunk of memory, bigger than the first by some (other?) default amount,
and copies everything in the first chunk into the second, and then
continues to fill the second. If that is still too small, then the
process is repeated until the entire database is in memory in a
continuous chunk of memory. By giving him the recommended "number of
objects +20%" to start with you bypass having to bootstrap your way to a
good size that will hold everything and still allow for new node discovery
and database changes. I am told that if ovwdb runs out of memory to hold
the object db when he is up and running, then he will go through this
"allocate and copy" process and that could hang the whole box until it is
done. Moral of the story they tell me is to set the default size the way
we recommend.
If you are happy with your results doing it the other way, fine. But if
it causes you problems, and you call Support, they will insist you do as
we recommend.
James Shanks
Level 3 Support for Tivoli NetView for UNIX and NT
Tivoli Software / IBM Software Group
"Davis, Donald" <donald.davis AT firstcitizens DOT com>
04/24/2002 03:45 PM
To: "'Allison, Jason (JALLISON)'" <JALLISON AT arinc DOT com>,
"'nv-l'"
<nv-l AT lists.tivoli DOT com>
cc:
Subject: [nv-l] RE: [OVWDB] cache size
Allison,
I stand corrected. (I hope) I just looked in the v6 manual and the ovwdb
cache size set to zero is also documented there. I guess it was fixed and
I just didn't know about it.
Don Davis
-----Original Message-----
From: Davis, Donald
Sent: Wednesday, April 24, 2002 3:38 PM
To: 'Allison, Jason (JALLISON)'; 'nv-l'
Subject: [OVWDB] cache size
Allison,
I haven't looked at the manuals for v7 yet. But, are you saying that the
manual is now advising to set the cache size at zero for automatic cache
adjustment??? That surprises me!!! I know it was a cool feature up through
aprox v4. At some release thereafter it didn't work.
My experience with setting it to zero was that once you exceeded an
arbitrary number of objects in the object database it stopped
auto-adjusting. I had a PMR opened for it a couple of years ago. The
solution was to always hard code the cache size appropriately and do not
use zero. This was truly an undocumented feature because that is exactly
what they did. They removed the documentation regarding setting the cache
size to zero from the Administrators Guide.
Now you say it is back. I hope it has been fixed!!!
Don Davis
-----Original Message-----
From: Allison, Jason (JALLISON) [mailto:JALLISON AT arinc DOT com]
Sent: Wednesday, April 24, 2002 3:17 PM
To: 'nv-l'
Subject: RE: [nv-l] Netview 7.1.1 Web Interface
How many nodes do you have?
You may want to check your cache sizes to make sure enough memory is
allocated for your instance of Netview. We just went through the same
process. The default for our Netview was 5000 objects. It took us 4 and
1/2 mintues for Netview to complete its "Map Synchronization" process
during
startup. We determined the DB had over 6000 objects (using the OV
commands). We performed many cleanup processes from /usr/OV/bin and
changed
the DM cache size to 0 (0 will let Netview determine dynamically the size
it
wants to use). After changing the cache size, the time went from 4.5
minutes to 45 seconds. If "May Syncronization" slowness is you problem
like
it was ours, you will see "Synchronizing" on the bottom left of the TME10
display. While this is happening during startup, the TME10 display is
basically non-responsive.
FYI, all of this is documented in the Netview Manuals.
Best of luck,
Jason Allison
Principal Engineer
ARINC Incorporated
Office: (410) 266-2006
FAX: (410) 573-3026
-----Original Message-----
From: Herman.E.Caballero AT Lowes DOT Com [mailto:Herman.E.Caballero AT Lowes
DOT Com]
Sent: Wednesday, April 24, 2002 3:01 PM
To: nv-l AT lists.tivoli DOT com
Subject: [nv-l] Netview 7.1.1 Web Interface
Have installed Netview for first time ever on an AIX box. Looks like the
Web interface is working ok, but it is very slow coming up. We were
considering using the Web interface for the NOC station, but we can't live
with how slow it takes to come up. Is there additional configuration that
I
don't know about that needs to be done?
When I had Netview 7.1 on an NT Server, it came up quickly. Any ideas?
Thanks,
Herman Caballero
Lowe's Companies, Inc.
Communications
336-658-4147
---------------------------------------------------------------------
To unsubscribe, e-mail: nv-l-unsubscribe AT lists.tivoli DOT com
For additional commands, e-mail: nv-l-help AT lists.tivoli DOT com
*NOTE*
This is not an Offical Tivoli Support forum. If you need immediate
assistance from Tivoli please call the IBM Tivoli Software Group
help line at 1-800-TIVOLI8(848-6548)
---------------------------------------------------------------------
To unsubscribe, e-mail: nv-l-unsubscribe AT lists.tivoli DOT com
For additional commands, e-mail: nv-l-help AT lists.tivoli DOT com
*NOTE*
This is not an Offical Tivoli Support forum. If you need immediate
assistance from Tivoli please call the IBM Tivoli Software Group
help line at 1-800-TIVOLI8(848-6548)
------------------------------------------------------------------------------
This electronic mail and any files transmitted with it are confidential
and are intended solely for the use of individual or entity to whom they
are addressed. If you are not the intended recipient or the person
responsible for delivering the electronic mail to the intended recipient,
be advised that you have received this electronic mail in error and that
any use, dissemination, forwarding, printing, or copying of this
electronic mail is strictly prohibited. If you have received this
electronic mail in error, please immediately notify the sender by return
mail.
==============================================================================
|
