[SOLVED] Rrd4j no charts. mapdb yes charts

Add-ons Persistence Services
1

Hello
sitemap chart line:

	Chart item=item_camara_int_temp_77 label="Temperatura"	period=h service="rrd4j"

If I select mapdb service, I do get a chart. A horizontal line, obviously. Below is my REST querry.
.rrd files DO get updated. but it would seem they only have 1 point.
I’m very confused, help!

#### Curl

curl -X GET --header "Accept: application/json" "https://192.168.12.44:8443/rest/persistence/items/item_camara_int_temp_77"

#### Request URL

https://192.168.12.44:8443/rest/persistence/items/item_camara_int_temp_77

#### Response Body

{
“name”: “item_camara_int_temp_77”,
“datapoints”: “1”,
“data”: [
{
“time”: 1574107069112,
“state”: “16.3”
}
]
}


#### Response Code

200

#### Response Headers

{
"content-length": "98",
"content-type": "application/json",
"server": "Jetty(9.4.11.v20180605)"
}
2

Please show your rrd4j.cfg file

3

it’s the default one

# configure specific rrd properties for given items in this file.
# please refer to the documentation available at
# https://www.openhab.org/addons/persistence/rrd4j/
#
# default_numeric and default_other are internally defined defnames and are used as
# defaults when no other defname applies

#<defname>.def=[ABSOLUTE|COUNTER|DERIVE|GAUGE],<heartbeat>,[<min>|U],[<max>|U],<step>
#<defname>.archives=[AVERAGE|MIN|MAX|LAST|FIRST|TOTAL],<xff>,<steps>,<rows>
#<defname>.items=<comma separated list of items for this defname>
4

Sorry I meant you rrd4j.persist file.

5

That COULD be due to your REST query with the default 24 houre timeframe. If you use that before more then one value has been saved to the archive 2 ( the one that covers 24 houres with one value every 4 minutes) you will get only one point.

However, as @vzorglub posted, show us your rrd4j.persist file. You might be missing the MANDATORY everyMinute strategy.

@vzorglub: Common failure, I always mix up .cfg and .persist file​:rofl::rofl:

6 
Strategies {
 everyMinute : "0 * * * * ?"
 everyHour : "0 0 * * * ?"
 everyDay : "0 0 0 * * ?"
 every15min : "*/15 * * * * ?"
 default = everyChange
}

Items {
genv* : strategy = restoreOnStartup, everyChange
item_camara_int_temp_77* : strategy = restoreOnStartup, everyChange

and from default.items:

Number item_camara_int_temp_77      "Temperatura interioara camara [%.1f °C]"   <temperature>   (genv, gtemp)  { channel="mqtt:topic:NodeMCU-V3-8266-camara:temp-int-77", expire="10m" }

hmmm…am I misssing everyMinute? in strategy?

7

Yes. You must have everyMinute in your strategy.

2 Likes
8

Yes you are.
To use rrd4j persistence in openHAB you MUST use the everyMinute parameter
As per the docs… https://www.openhab.org/addons/persistence/rrd4j/

9

it should have worked even with everyChange, not?

I added everyMinute, waited a few minutes and I get the same result

"name": "item_camara_int_temp_77",
  "datapoints": "1",
  "data": [
    {
      "time": 1574154779733,
      "state": "16.3"
10

ok so it’s working now. also graphs start to populate.

{
  "name": "item_camara_ext_temp_76",
  "datapoints": "2",
  "data": [
    {
      "time": 1574155680000,
      "state": "12.475000000000001"
    },
    {
      "time": 1574155920000,
      "state": "13.0"
    }
  ]
}

what got me confused was that the previous queries were without service specified, and it defaulted to mapdb, that’s why I always got 1 datapoint, and indeed that was being updated on every change

so, for anyone reading this: if rrd4j is NOT the default service, you have to manually add it to REST query using serviceid parameter

Thanks!

11

Cool, please tick the solution post
I have changed the topic to persistence

12

I just found this. I don’t think the docs say that the everyMinute parameter is obligatory :thinking:

13

This is correct. It was in the last paragraph of the 2.5 docs. It has been omitted in the latest docs. :thinking: