How many ActiveX processes can I have?

7 Mar 2006 2:16 PM

Martin

How many ActiveX processes can I have tied in to a single "master"
process?

I have several installations running where the application consists of
a "master" process and a single ActiveX process. The reason I do it
this way is to take advantage of the benefits of multi-threading in
dealing with "real time" interaction that the app is involved with
(receiving data from barcode scanners and exchanging data with other
computers). I've had zero problems with this approach.

I'm starting to develop a new app that's a little more complex than
previous ones and am considering using a master process and perhaps 3
or 4 ActiveX processes - each one handling different parts of the
real-time communications. Is this feasible? Is it practical?

Any advice?

7 Mar 2006 3:18 PM

J French

On Tue, 07 Mar 2006 07:16:23 -0700, Martin <martinval***@comcast.net>
wrote:

>How many ActiveX processes can I have tied in to a single "master"
>process?
>
>I have several installations running where the application consists of
>a "master" process and a single ActiveX process. The reason I do it
>this way is to take advantage of the benefits of multi-threading in
>dealing with "real time" interaction that the app is involved with
>(receiving data from barcode scanners and exchanging data with other
>computers). I've had zero problems with this approach.

You do know that if one AX EXE calls another, in effect the two
threads become one ?

>I'm starting to develop a new app that's a little more complex than
>previous ones and am considering using a master process and perhaps 3
>or 4 ActiveX processes - each one handling different parts of the
>real-time communications. Is this feasible? Is it practical?

Could be
- personally I would just make them separate normal EXEs and do away
with the AX rubbish
- it just confuses the issue

7 Mar 2006 4:38 PM

Martin

On Tue, 7 Mar 2006 15:18:50 +0000 (UTC), erew***@nowhere.uk (J French)
wrote:

Show quoteHide quote

>On Tue, 07 Mar 2006 07:16:23 -0700, Martin <martinval***@comcast.net>
>wrote:
>
>>How many ActiveX processes can I have tied in to a single "master"
>>process?
>>
>>I have several installations running where the application consists of
>>a "master" process and a single ActiveX process. The reason I do it
>>this way is to take advantage of the benefits of multi-threading in
>>dealing with "real time" interaction that the app is involved with
>>(receiving data from barcode scanners and exchanging data with other
>>computers). I've had zero problems with this approach.
>
>You do know that if one AX EXE calls another, in effect the two
>threads become one ?

No, I didn't know that but I don't think this will be an issue. The
way I see it working is that each AX will talk only with the master
process.

Also, the way I have things set up now, if I call the AX thread with
something that is going to require any amount of processing, I dump it
in to a timer and allow the connection between the two processes to
end. A few milleseconds later, the timer fires and allows the
processing to take place in the AX. I would assume that I could do
something similar if I had to call one AX from another.

>>I'm starting to develop a new app that's a little more complex than
>>previous ones and am considering using a master process and perhaps 3
>>or 4 ActiveX processes - each one handling different parts of the
>>real-time communications. Is this feasible? Is it practical?
>
>Could be
>- personally I would just make them separate normal EXEs and do away
>with the AX rubbish
>- it just confuses the issue

I actually did things this way in a couple of instances but it made
things more complicated and confusing for the end-user. He had to
understand that for the "application" to work, there had to be
multiple programs running. Once I learned how to get AX processes to
work, all that's become transparent to him.

In fact I even have a couple of installations where I have multiple
processes and one of them has an "attached" AX process.

7 Mar 2006 3:42 PM

Ken Halter

Show quote Hide quote

"Martin" <martinval***@comcast.net> wrote in message
news:5a5r02l1u714be7l00cf9cia593jdnhbkg@4ax.com...
> How many ActiveX processes can I have tied in to a single "master"
> process?
>
> I have several installations running where the application consists of
> a "master" process and a single ActiveX process. The reason I do it
> this way is to take advantage of the benefits of multi-threading in
> dealing with "real time" interaction that the app is involved with
> (receiving data from barcode scanners and exchanging data with other
> computers). I've had zero problems with this approach.
>
> I'm starting to develop a new app that's a little more complex than
> previous ones and am considering using a master process and perhaps 3
> or 4 ActiveX processes - each one handling different parts of the
> real-time communications. Is this feasible? Is it practical?
>
> Any advice?

Sounds a lot like a project of mine. Basically, it consists of a single exe
and 4 instances of an ActiveX exe. Those ActiveX exe's handle TCP-IP
communications to/from 4 separate controllers.... which, in turn, control 24
stepper motors (6 each * 4).

There's really no such thing as "Real Time" though if you're running
Windows. You can get "nearly Real Time" with a high performance PC and a lot
of ram but there's still OS overhead, task switching, etc, to deal with.

--
Ken Halter - MS-MVP-VB - Please keep all discussions in the groups..
DLL Hell problems? Try ComGuard - http://www.vbsight.com/ComGuard.htm

7 Mar 2006 4:46 PM

Martin

On Tue, 7 Mar 2006 07:42:44 -0800, "Ken Halter"
<Ken_Halter@Use_Sparingly_Hotmail.com> wrote:

Show quoteHide quote

>"Martin" <martinval***@comcast.net> wrote in message
>news:5a5r02l1u714be7l00cf9cia593jdnhbkg@4ax.com...
>> How many ActiveX processes can I have tied in to a single "master"
>> process?
>>
>> I have several installations running where the application consists of
>> a "master" process and a single ActiveX process. The reason I do it
>> this way is to take advantage of the benefits of multi-threading in
>> dealing with "real time" interaction that the app is involved with
>> (receiving data from barcode scanners and exchanging data with other
>> computers). I've had zero problems with this approach.
>>
>> I'm starting to develop a new app that's a little more complex than
>> previous ones and am considering using a master process and perhaps 3
>> or 4 ActiveX processes - each one handling different parts of the
>> real-time communications. Is this feasible? Is it practical?
>>
>> Any advice?
>
>Sounds a lot like a project of mine. Basically, it consists of a single exe
>and 4 instances of an ActiveX exe. Those ActiveX exe's handle TCP-IP
>communications to/from 4 separate controllers.... which, in turn, control 24
>stepper motors (6 each * 4).
>
>There's really no such thing as "Real Time" though if you're running
>Windows. You can get "nearly Real Time" with a high performance PC and a lot
>of ram but there's still OS overhead, task switching, etc, to deal with.

Understood. I should have said "soft real time". I just need to get
stuff processed fast enough to keep up with product moving on a
conveyor system. I can't allow my program to get so bogged down
processing one activity that it completely misses another one

I'm encouraged by your comment that you have 4 AX's tied in to one
exe. That's probably what I'll end up with.

Thanks.

8 Mar 2006 11:50 AM

J French

On Tue, 07 Mar 2006 09:46:19 -0700, Martin <martinval***@comcast.net>
wrote:

<snip>

>I'm encouraged by your comment that you have 4 AX's tied in to one
>exe. That's probably what I'll end up with.

Just trash AX