I have an application in VFP5 (but I'm porting to VFP7)
working with a database of about 60 tables.
Some tables (8-10) may have a lot of records (300.000-500.000)
ad a big size (100-200 MB or more + Memos!!).
These are standard dbf tables accessed over the network in a
read/write shared environment.

Now my question is: how many users can reasonably access this
database at the same time?
Supposing network is 100Mb ad is working good, supposing all
network cards are PC doesn't have "problems", supposing I
can forget hardware problems, how could I evaluate the
max number of concurrent users can work in this context?

By now I reached about 20 users without problems, but I
don't know how to evaluate an upper limit. Maybe 50 or 100
ore more?
I think the main problem is not VFP itself but the server System.
It needs to have a lot of files opened in shared mode......


Thanks.

--
Andrea Mariottini

Andrea,
You are correct VFP sets no limits - concurrency will depend on you network server OS and network configuration.

Others have done much more - see http://www.universalthread.com/wconn...ormation~4,3,1 for some other apps and their capacities!

Rick

"Andrea Mariottini" <a.mariottini (AT) libero (DOT) it> wrote

Hi Andrea,

Why port to VFP7 when VFP8 is the current version. You'll love it!

--
Cindy Winegarden MCSD, Microsoft Visual FoxPro MVP
cindy.winegarden (AT) mvps (DOT) org, www.cindywinegarden.com

"Andrea Mariottini" <a.mariottini (AT) libero (DOT) it> wrote

Cindy Winegarden wrote:

Simply because VFP7 is more tested.

--
Andrea Mariottini

Rick Bean wrote:


Thanks Rick, this link is very helpful.
Do you have any idea on methods to evaluate/test
max concurrent user limit?
And how evaluate server ram, disks ecc....?

--
Andrea Mariottini

Andrea,
That might be better asked on a NT/2000/2003(/Novell?) server or hardware performance newsgroup, since it really has nothing to do FoxPro.

Rick

"Andrea Mariottini" <a.mariottini (AT) libero (DOT) it> wrote

I don't buy that. VFP8's been out for 9 months. I find it very stable and
haven't had much in the way of problems. There's a service pack due out any
day now.

Once the SP1 was out for VFP7, all the Microsoft VFP team's energy went into
VFP8, including fixing bugs from VFP7. More "testing" (i.e. being out
longer) doesn't equate to any more stability unless there are additional
service packs. I wouldn't want you to waste your time or your money on an
older version of FoxPro.

--
Cindy Winegarden MCSD, Microsoft Visual FoxPro MVP
cindy.winegarden (AT) mvps (DOT) org, www.cindywinegarden.com

"Andrea Mariottini" <a.mariottini (AT) libero (DOT) it> wrote

Cindy Winegarden wrote:

Thanks Cindy but I already have VFP7 because I used it
to develop others applications.
I don't have VFP8.
Moreover I know VFP8 has a different SQL engine and I would like
to bypass SQL problems by now. I know you can set a compatibility level
with VFP7, but before porting an existing application I would prefer
to make some experience before.

--
Andrea Mariottini

Rick Bean wrote:

Yes, it has to do with the way VFP read/write/lock files or part of files.

--
Andrea Mariottini

Andrea,
No, VFP doesn't do any reading, writing or locking - it simply asks the OS to do it, whether locally or on the file server. How these are done, not only depends on the OS, but the drivers and hardware that's being used.

Rick

"Andrea Mariottini" <a.mariottini (AT) libero (DOT) it> wrote