In that case I would bring it right down to 5 or 10 secs, in fact i would even try 1 or 0 seconds if it were me, but i do not know if the 0 or 1 would definitely work, hence the suggestion of a more relaxed 5 or 10s, there is no reason that wouldn’t work and no reason to buffer data any longer than that just to get the ability to pause writing data to a hdd.
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Also, just FYI, I have in the past, just unmounted my data folder (I have a partition purely for data) and emoncms has continued to buffer data in redis (I do not have feedwriter installed/running) until i remounted the data partition/folder. I have no idea how long that might work, it’s not a recognised method. But the advantage of this is that the characteristics of the feeds are not altered.
When feedwriter is enabled you cannot edit/post data older than the last entry. And more specifically with phpfina feeds, when multiple updates occur within the duration of a given fixed interval, with feedwriter enabled, the first presented is kept, whilst when not enabled, the last update is kept.
It’s a small thing, but it can cause confusion if you are not aware.