Extraneous MiOS items - system lag?

I used the MiOS Item Generator, and it worked great. It created items for all sorts of statuses and things that I didn’t know were available on the Vera, and some of those things will be very helpful when creating rules.

On the other hand, there are also a bunch of items that don’t seem to do anything, for instance, the Device ID items. Is it safe to remove these from the .items file? Or do they perform some background function that is required?

I’m noticing some significant lag (3 to 5 seconds) when using a scene controller to trigger rules, and based on what I see in the events.log, the lag seems to be on the rule processing side of things, not the Z-wave/communications side… are these extra items and their associated updates bogging down my RPi2? When I look at my events.log, I see constant updates to the device ID… but it’s always “updating” to the same number. Are these updates consuming system resources? Does simply having the items in the .items file add to the burden on the system?

You can safely remove anything you’re not using, but it’s more convenient to just comment out those lines (so you can add them back later)

The ID Items that are generated for each MiOS Device will always update to the same value and are updated at the end of updating ALL attribute/item values for that Device…

This is sometimes used as a scene/rule trigger (mostly when you have cross attribute dependencies as can happen with MiOS Alarm Panel devices)

If you don’t (yet) need that functionality then feel free to comment out those generated Items.

In general openHAB will log a lot of stuff. This can be somewhat dialed back, but logging (and persistence) can take a toll on slower IO subsystems. The RPi can have slow IO, esp if you’re using the SD card (instead of a USB Stick)

That said, unless you have Debug logging enabled, or a lot of persistence configured, you wouldn’t normally notice.

For reference, I have 1000+ Item definitions in my system, using an Odroid C1+ and eMMC. I persist all attributes using MapDB and some with RRD and I run with DEBUG login permanently.

…And there aren’t any noticeable delays. :slight_smile:

Cool, thanks. I’ll definitely comment out the extra items for now, and hopefully I’ll be able to figure out what else needs to happen to reduce the lag on my scene controller buttons. Probably my first step will be to move off of the SD card and onto a USB stick or a powered external drive.