I expect I'm being thick or just tired but I am having a problem with persistent context stores. No, I'm not being thick, I can see the problem happening. It is because there is a delay of around 30 seconds before persistent variables are written to the fs. While that is fine normally, Node-RED, I …

You can always change the flush interval; contextStorage: { default: "file", memoryOnly: { module: 'memory' }, file: { module: 'localfilesystem', config: { flushInterval: '10' }, }, },

How are you stopping Node-RED? If you are just killing the process abruptly, then you don't allow the file store to flush it's contents.

[image] Paul-Reed: You can always change the flush interval; Thanks for the reminder. [image] knolleary: How are you stopping Node-RED? If you are just killing the process abruptly, then you don't allow the file store to flush it's contents. Well, I'm mainly using nodemon so I'd expec…

What signal does nodemon use to kill the process ?

You had to go and ask didn't you! Well a quick look through the code found this: const restartSignal = config.options.signal === 'SIGUSR2' ? 'SIGHUP' : 'SIGUSR2'; There may be more, I'll look further. And there is a bunch of code around here that looks like it is using kill with a signal code: …

[image] TotallyInformation: I'm also reluctant to change the flushInterval as per Paul's code as I'm not sure of the performance impac I've actually increased my flush interval for my pi (running on a SD card). I've just tested whether my 'script installed' installation of node-RED writes it…

It's good to know when it does and doesn't so we probably need to create a full list for the documentation so that people don't get caught out. Thanks for doing that research Paul. I realise that my use-case is rather "edge" (typically me) but I think people should at least be aware. I do also th…

Julian at the bottom of red.js we have process.on('SIGINT', function () {... can you try just duplicating that block and changing one to SIGUSR2 ?

The docs do already say this: The flushInterval is provided to minimise wear on the underlying storage, such as on a Raspberry Pi’s SD card. Note that if Node-RED is unexpectedly killed, any data that has not yet been flushed will be lost. https://nodered.org/docs/api/context/store/localfilesy…

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A catch with persistent file stores

General

drmibell 30 January 2020 23:32 4

This issue seems to have come up before, and presumably was resolved in version 0.20. Or is this something new?

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A catch with persistent file stores

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