archiving - values not changing, but archive keeps updating every 3sec

[tpjctrl]

I've setup archive configs on over 20k datapoint elements and noticed that there's new entries in the archive roughly every 3sec regardless of whether the values for the elements change or not. So for example if I run a query to get all off line values for the last 30min it returns a growing amount of results every single time it's ran. Now of course with over 20k elements being archive this fills up the flat file rather quickly.

Is there a way to only archive on value change? I'm actually not sure why there's new archive entries being logged if no value change is detected, so feel free to reply with a reason : ) most of the 20k elements also have address configs and are setup for new / old comparison but I think there's so many datapoints in the system that this is ignored and all values are pulled in en masse ignoring any comparisons. Still there's a bunch of tags which don't have address configs and these also seem to archive every 3sec even though the values all stay the same pretty much all the time.

Regards,
T.

[leoknipp]

By reading the attribute _offline.._manager you can get the manager ID which has changed the value. With the CTRL function getManIdFromInt() you can convert the manager ID to a more useful information.

At the _archive config you can configure smoothing for the values, e.g. old/new comparison, time dependent smoothing, ....
The driver does not ignore the old/new comparison and/or smoothing options if there are many _address configs defined.

Please take into account that an old/new comparison for float values is not useful if the smoothing is made for the raw value.
In that case you can use the _,msg_conv config to reduce the amount of digits after the comma and afterwards you can use the options in the _smooth config.

Best Regards
Leopold Knipp
Senior Support Specialist

[tpjctrl]

Thanks for your reply Leopold.

What would be the reason for archives recording new values every few seconds without a change in value? Btw this is what happens to all points across the entire database, everything that has an address config will update every few seconds (3-4sec) even though the values don't change and new / old comparison is selected in all the address configs (it's easy to spot by looking at the constantly changing timestamp in the _common config). My guess is this is what triggers all the archive entries as the timestamps change constantly and the archive simply saves all the corresponding values. This is far from ideal of course as all active dpconnects will get triggered every few seconds even though there's no reason for it.

I'll have a look at smoothing values for now.

Regards,
Tom

[leoknipp]

In the _original panel (not the _common panel) in the PARA module you can see which manager has changed the value.
This information you can use for further analysis and to detect why the manager shown in the panel is triggering the dp element.

Best Regards
Leopold Knipp
Senior Support Specialist