Check this out,

http://social.technet.microsoft.com/Forums/en-US/smallbusinessserver/thread/ec937501-17d4-4e0f-adb3-04b4896358b2/

Dennis McGrath
Software Developer
QMI Security Solutions
1661 Glenlake Ave
Itasca IL 60143
630-980-8461
[email protected]
From: [email protected] [mailto:[email protected]] On Behalf Of Karen Tellef
Sent: Monday, December 17, 2012 4:34 PM
To: RBASE-L Mailing List
Subject: [RBASE-L] - Re: Slowness with 7.6, revisited

For anyone interested, I am going to copy below what I had saved over the years 
regarding Opportunistic Locking.  It does seem to mention Novel alot though...  
 The link in the first posting, which was Mike B's, brings you to a search list 
of articles.  The asterisks separate comments from different people.

Karen

I have seen posts on this subject in the past and at one time I had the 
documentation on it but couldn't find it.  Today I stumbled upon the problem 
and the solution AND the explanation for the fix on various links from The 
Google search below.  Anyway the problem was related to file corruption in 
multiuser scenarios using WindowsNT4 and Window2K servers.  The various links 
show the registry settings that will turn on/off Opportunistic Locking and Set 
the Cache Size to force flushes.  I would pick your favorite and archive the 
document to a convenient location.....  (Mike Byerley)

http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&as_qdr=all&q=enable
oplocks+%22hkey_local_machine+system+currentcontrolset+services+lanmanserver
+parameters%22&spell=1
* * * * * *
Just this week, we had a Novell 5x server on life support that we had to 
immediately migrate to a new Novell 6x server. The migration had minor caveats, 
but went fairly well.

The first thing we observed was a remarkable improvement in execution speed of 
code as a result of the new hardware. However, the much feared "long pause when 
a second machine went to connect to the database" made its appearance after 
never having it happen before.   Ok, thankfully I remembered this thread and 
began to search for a similar setting on Novell. Needless to say, Novell 6x has 
two server level settings which mimic the Windows settings that Ben referred 
to.   Here are the settings that need added to the Autoexec.ncf file:

SET Client File Caching Enabled = OFF
SET Level 2 OpLocks Enabled = OFF

I can attest that the connection speed is night and day different, about 8-10 
seconds with both settings on, and 0-1 seconds with the settings off. It takes 
effect immediately after the client machines are rebooted. The server level 
settings override the client settings, so it is best to make a global setting 
change like this at the server.
* * * *
I have read blog after blog on various newsgroups about dBase, Paradox and 
other file-shared databases constantly experiencing corruption because of the 
opportunistic file locking, and it make complete sense.

On top of that, there is the potential that one user's changes would  not get 
immediately reflected in the database and another's could overwrite or 
conflict, again causing problems. File-shared databases are designed to control 
multi-user environments internally, and the influence of external intervention, 
like that from the network, is only
a problem waiting to happen. The way I see it is that if you are using a 
file-shared database system like R:BASE or others, you have NO option but to 
disable these settings to prevent major problems.
* * * * *
I was able to execute the first command
   SET Client File Caching Enabled = OFF
from the system console.  The second command
   SET Level 2 OpLocks Enabled = OFF
did not work from the system console.  It gave an error message

>From what I gather, the Level 2 OpLocks is available only in more recent 
>versions of Netware. What you could do to see if it exists in your version is 
>to type SET at the console and then look for the NCP option, it should be 
>number 8. Type 8 and then use your up arrow to scroll through to options and 
>see if it exists. If it does, check
your syntax for errors. It isn't exclusive to the Autoexec.ncf file.

I don't know how things work with one disabled and the other not because I 
disabled both at the same time. We are running a very robust server and 
network, so the visible performance hit is only slight. The larger concern for 
us is to prevent possible database corruption because we have a much larger 
client base.





Reply via email to