Which is better to use? NOW or TIMER?

Plugins & Plugin Development Program Logic (PLEG)
1

Hi Richard,

I have a general question:

Let’s assume I want condition2 to become true 30 minutes after condition1 becomes true.

What is the difference between using “NOW”, for example:

Condition2 = (Condition1;NOW>30:00) AND ......

and using a 30 minutes timer, that will be fired up as an action of condition1, and set:

Condition2 = NOT(30MinTime) AND ......

Does any one makes PLEG use less CPU? Memory? Other effect on the Vera unit?

Thanks!

2

NOW is easier to use (no external timer) however it’s resolution is 1 minute.

3

Thanks for the quick reply.

Any information with regards to performance?

As you know (from a different thread), my Vera is going through many restarts every day.

Since I have many conditions using “NOW”, I was thinking that maybe moving them to use timers will “help” Vera use less memory/cpu, as PLEG will not have to evaluate the condition every minute.

Is that true, or there is no performance difference between the two?

4

NOW should not be a significant load on Vera …
If that does make it go over the top … it would likely go over the top on other events as well.

You will more likely increase stability by reducing the total count of plugin devices.
What type of Vera do you have ?

5

Lite ::slight_smile:

So you wouldn’t recommend investing the time to transform conditions using NOW to conditions using timers?

6
Lite ::)
I suspected ... so I would recommend that removing the number of non-child plugin devices will more likely reduce the load.

This is any device on Vera, where the controlling device is not specified in the Advanced tab.
Your Z-Wave devices are OK.

Other options are:
Add USB for logging.
Remove the Energy plugin if you are using it.

7

If I would like to keep all those plugins (and even add additional ones) - will replacing the Vera Lite with Vera 3 solve the restarting issues?

8

if you can find a Vera 3 that would b the way to go.

or wait until UI7 is more stable then you can use a Vera Edge.

9

OK. And in the meanwhile, should I convert the NOW to timers, or not?

10

It will not likely change the stability issues.

11

Does this mean that having, say, 4 separate PLEG devices would require less resources than 1 device would require with the same amount of data in both scenarios?

12

When comparing 4 PLEGs vs 1 PLEG with all of the merged logic of the 4

The 4 PLEG solution will use more Memory and likely less CPU
The 1 PLEG solution will use less Memory and more CPU

Vera is MOSTLY memory limited so merging PLEGs is a good option if you are having memory problems.
If you are not having memory problems, then more PLEGS will save you some CPU time.
We are NOT talking about a lot of CPU time savings in either case.
But the memory savings are critical if you are having memory related reloads.

13

Thanks Richard