How many concurrent users in an MS-Access client/server based app.

[Guest]

I'm having some concerns about the number of concurrent users we can safely
have in an MS-Access application that is client-server based. I've heard
numbers ranging from 5 to 255. The database stored on the server is not
large but there is a fair amount of activity on it. We've changed NIC/Switch
duplex settings, we've increased the MAXLOCKSPERFILE on both w/s and server,
but are still seeing some slow response with app. 35 concurrent users.

Any Advice???

 

[Albert D. Kallal]

I'm having some concerns about the number of concurrent users we can
safely
have in an MS-Access application that is client-server based.

Actually, ms-access when used as a file share is not considered a client
server application, but is really just what we call a "file share". This
means that processing occurs on each pc..where as in client->server, data
processing occurs on the server BEFORE the data is sent to each workstation.
(this is not a big deal..but I do want you to get the terminology right..as
there is a VERY big difference between a client server application, and a
file share application like ms-access. It also means a very different way in
how data is sent, and updated. Also, note that ms-access CAN be (and often
is) a client in a client to server database setup. That means the front end
part is ms-access, and the back end part is sql-server, Oracle, or your
favatore database server engine. So, to be fair..it is possible that you are
in fact using a client to server setup..but not enough information was given
by you to determine this. (it certainly seems we are talking about a file
share here).

I've heard
numbers ranging from 5 to 255. The database stored on the server is not
large but there is a fair amount of activity on it. We've changed
NIC/Switch
duplex settings, we've increased the MAXLOCKSPERFILE on both w/s and
server,
but are still seeing some slow response with app. 35 concurrent users.

Any Advice???

With a proper setup, you can easily run 20 users.

You don't mention after how many users the application slows down. Is the
application just fine with 2, or 3 users..and then at 10 users it is slow?
(you need to give more information in this regards). I mean, if the
application is slow with just 2 users...then lets fix that before we start
worrying about 35 users.

So, #1 question is after how many users does the application start to slow
down? Can you run 10 fine, but 20 is to slow?

#2, what is the speed of your network...is it a 10 base, 100 base, or 1gig
base?

#3, do you have a correct multi-user setup? That means that you are running
a split application, and EACH WORKSTATION gets a copy of the application
part, and the data part is placed on the server. Further, each workstation
should get a mde. This means you CAN NOT allow multiple users into a same
front end at the same time. Each user gets their OWN COPY of the front end,
and this is placed on EACH workstation.

Further, if you do have a split database..have you tried a persistent
connection..this can do INCREDIBLE things for speeding up response time.

You also don't mention what version of ms-access. However, there is a great
performance faq of things to try (assuming you got the above points already
correct).

http://www.granite.ab.ca/access/performancefaq.htm

 

[Guest]

Hi Albert...

Ok here goes...
Our application is indeed a file share and not a client/server
application. The .mde, a code table and a "client" .cli file sit on the
user's C: drive

1. We have run the app. on both app's servers and file/print servers and
the application usually slows down after 15-20 concurrent users, depending on
the activity that they're performing (updates, searches). We need to run the
application quickly with between 30-40 users. (We are in the process of
moving the back end to SQL but keeping the front end Access.)

2. The network(s) all run at 100Base, but in some instances we have pretty
horrendous infrastructure. We have replaced NIC's, Switches, and cabling in
all bad sites and have hard-coded the Switch & Server NIC settings to 100
Full Duplex from Auto Detect.

3. The drive on the share is persistently mapped from all workstations
accessing the database.

We are running Access 2000 and the Jet Engine is 4.0 with SP5

Any more help that you can offer would be greatly appreciated. Thanks Again!!

Grant