Professional OPC
Development Tools

logos

lupa

Online Forums

Technical support is provided through Support Forums below. Anybody can view them; you need to Register/Login to our site (see links in upper right corner) in order to Post questions. You do not have to be a licensed user of our product.

Please read Rules for forum posts before reporting your issue or asking a question. OPC Labs team is actively monitoring the forums, and replies as soon as possible. Various technical information can also be found in our Knowledge Base. For your convenience, we have also assembled a Frequently Asked Questions page.

Do not use the Contact page for technical issues.

  1. Forum
  3. Discussions
  5. QuickOPC-Classic in .NET
  7. Connections, Reconnections, COM/DCOM
  9. Connecting to many OPC-servers using multiple threads gives Timeouts

Connecting to many OPC-servers using multiple threads gives Timeouts

More
02 Sep 2020 09:39 #8825 by zaglerp
Replied by zaglerp on topic Connecting to many OPC-servers using multiple threads gives Timeouts
Hello,

thank you, I tried your suggestions.
If I request all nodes using a single call it takes approx 50 seconds and some servers have a timeout.

Why do I get timeouts here? All servers are up and running.
And when requested sequentially everything is working fine...

Kind regards
Peter

Please Log in or Create an account to join the conversation.

More
02 Sep 2020 09:22 #8824 by support
Replied by support on topic Connecting to many OPC-servers using multiple threads gives Timeouts
Hello,
I am not sure about the behaviors you have described, that would require more investigation, but none of them is the one we recommend.

The recommended approach is to call a single MultipleRead with all the target OPC servers, and let QuickOPC sort out the rest.

Best regards

Please Log in or Create an account to join the conversation.

More
02 Sep 2020 07:58 #8822 by zaglerp
Connecting to many OPC-servers using multiple threads gives Timeouts was created by zaglerp
Hello,

I try to do a MultipleRead (with 19 values) from 30 OPC-Servers running on 30 different hosts. THese servers are all up and running.
The behaviour is unclear to me:

1. Using 30 C#-Tasks running in parallel:
The whole process completes after approx. 51 seconds. At least one OPC-Server returns a timeout error (BadRequestTimeout)

2. Using 30 C#-Tasks running in sequence (using a lock):
The whole process completes after approx. 41 seconds until all Reads are completed. All OPC-server are working - no timeouts.

Can you please clarify, why
- it is faster to do this in sequence than in parallel
- some Servers have a timeout when accessed in parallel

Which procedure to you suggest for implementing this?
I have attached my test program, written in C# and using 5.58.257.1
Line 54 contains a lock that was commented out for parallel access.

Thank you for your support.
Peter
Attachments:

Please Log in or Create an account to join the conversation.

Moderators: support
  1. Forum
  3. Discussions
  5. QuickOPC-Classic in .NET
  7. Connections, Reconnections, COM/DCOM
  9. Connecting to many OPC-servers using multiple threads gives Timeouts
Time to create page: 0.047 seconds