Child metric on charts only refreshed every 60 seconds

Help
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I am running 4 instances of NetData in my homelab; 3 are configured as children streaming to a single parent node. Looking at the NetData metrics for the streaming, you can see that there is a constant stream of data being sent from the children and as well as received by the parent. However, when viewing the charts from the parent node, data from the children is only updated every 60 seconds at second 0 of each minute. Watching a live chart, each minute a gap in data build from the right until the next minute when the gap from the previous minute if filled in. While the gap is present, information shows either “Partial Data” or “Empty Data” depending on whether or not the chart includes data from the parent which is always timely.

Early on, I was not streaming to the parent, all 4 nodes were connected to NetData Cloud. In that configuration, I don’t recall seeing this happen. I suspect there is some configuration tweak I need, but I cannot find it. Any help would be greatly appreciated!

UPDATE:
After continued digging, I see that the streamed child metrics is at the 60 second resolution while the parent’s metrics are at the 1 second resolution. I cannot find any documentation that suggests this is the intended behavior.

2

Solved!
My misunderstanding of the stream configuration was the cause. I mistook the “default memory mode” setting in the stream.conf to be the setting to be used on the connected child. As such I had it set to “none” for a headless configuration. It is not. This is wrong.
The “default memory mode” is the type of storage to use for the child’s metrics when they are stored on the parent. That should have been set to “dbengine”. Setting the db mode to “none” for the children should be done in the netdata.conf file as [db].mode = none.
Charts now have all the fidelity (1-sec) regardless of the source node of the metrics!

1 Like
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Welcome!!

Was just going to respond but see you sorted it.

Thanks for sharing your solution as am sure it will help someone else in future - the parent child configs confused me a bit when i first was trying to figure them out too - can be hard to be clear in your head what config goes on child and what goes on parent etc :slight_smile: