[BUG-13959] Query Tags don't refresh per the leased rate

There seems to be at least a couple issues.

  1. Neither the query tags or the opc items seem to update per the leased rate.
  2. The query tags seem to update on a separate interval as the opc item it is populating.

I couldn’t replicate an issue (using the current 8.0.2 build). For query tags, you do have to have a few things in a row:

  1. Tag group set to Leased.
  2. Tag set to the leased tag group
  3. Execution Mode set to “Tag Group”.

With OPC, step 3 isn’t necessary.

Now, there IS a big change between 7 and 8: The tag browse tree no longer causes the leased state to become active. So in order for a tag to be “leased”, it has to be used and open on a vision window, perspective view, etc.

One other thing about OPC- sometimes timing can be a bit off of what you’d expect (but should always be at least what you want, if not faster) based on other subscriptions, especially if the same path is subscribed in different tag groups. It’s just something else to keep in mind.

If all of this checks out and you’re still having a problem, we can try to dig in more to what your exact settings/state is.

Thanks. I’ll have to call into support. The query tags are used on the window so they should be leased, and the leased rate is 2 seconds. It seems to be anywhere from immediate to upwards of 30 seconds for the query tags to update.

Is it possible that one or more of your queries is slow (even occasionally) and that's why you're seeing slow updates?

Check out the Status > Tags > Groups tab and see what the execution times are for the group with the query tags.

Interesting. None of my tag groups show execution/duration times.

I am running the 5/15 nightly.

Hmm, I think the missing diagnostics are a bug.

Query tags are refreshing quickly this morning, so maybe there was a performance issue going on that wasn’t obvious. Thanks!

This issue was fixed in the 8.0.3 nightly build from 5/23.