Hi,

I've noticed when running DBISam in local mode across a network that when 1
user is connected to the server, things run relatively fast. When more
connection are established (up to say 15) the whole database application
runs so much slower.

(This is running in Local mode, as opposed to Client/Server mode).

The interesting thing is - all the other 14 computers may be idle, but just
being connected to the server causes the network to run slower.

This is not isolated to DBISam either - it also occurs with Paradox tables
through the BDE.

I know this isn't a DBISam issue - but I was wondering if anyone has come
across this problem and knows what the cause is, or even better - if they
can recommend a fix.

I know that multiple users collecting and saving data off the server at the
same time should slow the network, but I struggle to see why 14 idle
computers will still cause the network to run slower, just by being
'connected'.

The workstations are either Win2K or WinXP, and the servers range from NT4
to Win2003. (Same problem occurs at multiple sites).

Thanks & Regards

Adam.

--
There is a principle which is a bar against all information, which cannot
fail to keep a man in everlasting ignorance-- that principle is contempt
prior to investigation." - Herbert Spencer, British philosopher.
There is a second principle which has the same results as the 1st - that
principle is not caring about being ignorant" - Unknown

Hi Adam,

Check out this:

http://support.microsoft.com/default.aspx?scid=kb;en-us;Q129202

Chris Holland

Adam H. wrote:
> Hi,
>
> I've noticed when running DBISam in local mode across a network that when 1
> user is connected to the server, things run relatively fast. When more
> connection are established (up to say 15) the whole database application
> runs so much slower.
>
> (This is running in Local mode, as opposed to Client/Server mode).
>
> The interesting thing is - all the other 14 computers may be idle, but just
> being connected to the server causes the network to run slower.
>
> This is not isolated to DBISam either - it also occurs with Paradox tables
> through the BDE.
>
> I know this isn't a DBISam issue - but I was wondering if anyone has come
> across this problem and knows what the cause is, or even better - if they
> can recommend a fix.
>
> I know that multiple users collecting and saving data off the server at the
> same time should slow the network, but I struggle to see why 14 idle
> computers will still cause the network to run slower, just by being
> 'connected'.
>
> The workstations are either Win2K or WinXP, and the servers range from NT4
> to Win2003. (Same problem occurs at multiple sites).
>
> Thanks & Regards
>
> Adam.
>

Hi Chris,

Thanks for your reply. In the instances I have, it is apparently not
oplocking, which is what has me so confused.

Thanks & Regrds

Adam.

Adam,

<< Thanks for your reply. In the instances I have, it is apparently not
oplocking, which is what has me so confused. >>

It is most likely indeed OpLocks that is causing the behavior that you're
seeing.  OpLocks behavior is basically just as you describe:

- with one person using a file, the file access is very fast because data
from the file is cached locally since there is no chance that another user
will change the file

- once another person has the file open, the file access goes back to normal
network speed, and all reads/writes must be done across the network

--
Tim Young
Elevate Software
www.elevatesoft.com

Hi Tim,

Thanks for your reply. We must be doing something wrong in trying to disable
oplocks if that is the case. (Which could be the case).

At this stage, we have tried:

On workstations setting:
HKLM\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters
UseOpportunisticLocking = 0.
UtilizeNtCaching = 0
------
On the server:
\HKLM\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters
EnableOplocks = 0
CachedOpenLimit = 0
[HKLM\System\CurrentControlSet\Services\MRxSmb\Parameters]
OplocksDisabled = 1

The above seems to have made no difference at this point in time, even
though, as you stated, the behaviour does sound suspiciously like Oplocks.

Is there another registry setting we could be missing?

Thanks & Regards

Adam.

Adam,

<< Thanks for your reply. We must be doing something wrong in trying to
disable oplocks if that is the case. (Which could be the case). >>

I'm not sure you understand completely.  If you disable OpLocks, then the
access will *always* be slow, even with only one user.  OpLocks is primarily
intended to be a little speed booster for Word, Excel, etc. files that are
usually used by only one person at a time, but unfortunately have the
side-effect of doing the same to database applications, thus making the
performance seem better than it really is over the network when only one
user is accessing the database table.

--
Tim Young
Elevate Software
www.elevatesoft.com

Hi Tim,

Thanks for the clarification. Indeed you were correct - I had the wrong
idea. (I recalled oplocks causing problems with the BDE, so we used to
disable them - I thought that may have been the same thing).

Thanks for clarifying that for me Tim!

Regards

Adam.