I installed a Node-red on a Linux embedded device with limited space, and wrote some complex flowcharts. Through the "top" command in Linux, it was found that Node-red has a very high usage of virtual memory (exceeding 50% of the total). I extensively use flow. set ("data_name", data_val) in the f…

Yes, the memory space of embedded devices is relatively small, Thank you very much for your guidance. I have learned a lot~

[image] meeki007: To keep ram usage low you will need to set your flow/global vars to empty or null =, ={}, ="" when you are done using them. I think it would be Best to set them to undefined to remove the reference to them from memory. flow. set ("data_name", undefined)

Thank you for your suggestion. I just checked and found that I have called flow.set for 400 times. I need to check them one by one and set them undefined when appropriate. This is a major project ::

[image] E1cid: I think it would be Best to set them to undefined to remove the reference to them from memory. flow. set ("data_name", undefined) Can confirm: node-red/node-red/blob/ce5b6a8024533958f9ba68eb4df464e61c775bce/packages/node_modules/@node-red/util/lib/util.js#L512-L518 …

Thank you! That's amazing, just analyze the source code directly

I am trying to design a complex industrial control system using Node red, I have some requirements that may require separation operations to achieve: For example, using MQTT to send a request to the server, and then subscribing to the processing result. When it is determined to be successful, subs…

[image] Yesung: (1) Will variables set by flow. set() be automatically reclaimed (memory is automatically cleared)? No, not unless you set them to undefined or use a change node to delete them [image] Yesung: What method is required to manually clean variables? See previous [image…

On the other hand, industrial systems are constantly collecting data, and sensor data is constantly being updated, I wrote the data into the flow context so that the latest sensor data can be called from anywhere, So unfortunately, I used a lot of flow context

[image] Steve-Mcl: No different to any other application - but based on your post, I suspect you are using context too much and unnecessarily. Thank you very much for your detailed answer, Regarding this point, I would like to ask more, does "No different to any other application" means the …

How Node-red's memory recycling mechanism works

General

Colin 11 January 2024 09:00 12

This suggests that your design is not ideal. The node red way is to pass data using messages, then when a message is finished with the memory will be automatically reclaimed. Flow and global context should generally only be used when it is not practical to pass the data in messages.

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How Node-red's memory recycling mechanism works

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