Hello, I have a performance question. There are multiple methods of getting and setting variables. I would like to know what is adviced, or what gives the best performance between them. Question 1: what method is adviced: Method 1: single call var example1 = global.get('storedvariable1',"file"); …

Well, I do think most are needed. Some I could get away with flow, and also some are required to be in context. Not meant as an add or something, but the background (usecase) for this: I started using NR to communicate with my Panasonic heatpump. A lot of nice things to show, set and do. Also I h…

[image] edterbak: Does this also mean there is no benefit of having a variable 'xyz',"file" AND 'xyz',"memoryOnly". If the "file" variable is used, there is totally no need to have the same variable in "memoryOnly"? If you do that they are different variables.

[image] edterbak: By the nature of the project, I require settings to be stored so they are still available after reboot. Do you use MQTT?

different variable, with the same value... sounds to me like "overhead". correct?

No, Yes.. welll. I could do that, but I have already trapped into that error that values are retained and incorrect causing issues in the logic. I think I am better off using retain false, qos 0 to make sure I have the correct variables. For me, not fully understanding the effects and the rules r…

[image] edterbak: So; There is no benefit in reading one object containing multiple values vs multiple readings containing 1 variable. (apart from the coding itself) Not quite. Loading and Saving 1 object (full of your variables) is far quicker than calling flow.set or flow.get multiple time…

[image] Steve-Mcl: Not quite. Loading and Saving 1 object (full of your variables) is far quicker than calling flow.set or flow.get multiple times. This is due to several layers (plugin, path parsing, value extraction etc). When you get 1 object, it pulls only the reference from memory (not al…

[image] edterbak: Does this also mean there is no benefit of having a variable 'xyz',"file" AND 'xyz',"memoryOnly". If the "file" variable is used, there is totally no need to have the same variable in "memoryOnly"? That's right - the file store is really pretty much the same as the memory s…

Performance get/set variables. different methods

General

Colin 29 January 2023 18:02 13

In that case you could consider using Retained Topics in MQTT rather than context. It has the big advantage that when data changes you immediately get notified about the change.

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Performance get/set variables. different methods

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