Transformations randomly don't work properly

Grafana Stat Panel
1

Grafana 9.1.1
InfluxDB 1.8.3
Ubuntu 22.04

Hello,

I am using Stat Panel, with two queries, A and B.
In transformation tab I use “Binary operation” B / A.
Transformations are randomly not working, showing NaN as value, mostly when I select time period “Last X hours / Last X days”.

When this occurs, in debug window is visible that there is one empty value in values buffer which are used in Binary operation.

t2
t21506×601 38.7 KB

t3
t31511×608 35.8 KB

t4
t4860×775 26.3 KB

2

Instead of a Transformation, have you tried using an expression? (see example below)

image
image1221×892 57.9 KB

3

I tried, and it works. But it does not work as transformations, if query returns results from multiple measurements.
In transformation, data from multiple measurements can be combined to one value, and than do the math.
Using expression, it will do math with on every A value and every B value.

expression
expression1508×821 58.2 KB

4

A was able to reproduce this issue also on https://play.grafana.org/ in “InfluxDB Templated” dashboard, so I attach here panel JSON.
When I select “Last 15 minutes” panel returns “NaN” from B/A operation.
When I select “Yesterday” panel returns correct number value from B/A operation.

image

image

{ "id": 3, "gridPos": { "x": 0, "y": 0, "w": 24, "h": 5 }, "type": "stat", "title": "Panel Title", "targets": [ { "refId": "A", "datasource": { "type": "influxdb", "uid": "000000002" }, "policy": "default", "resultFormat": "time_series", "orderByTime": "ASC", "tags": [ { "key": "hostname", "value": "server1", "operator": "=" } ], "groupBy": [], "select": [ [ { "type": "field", "params": [ "value" ] }, { "type": "count", "params": [] } ] ], "measurement": "cpu", "alias": "A" }, { "refId": "B", "datasource": { "type": "influxdb", "uid": "000000002" }, "policy": "default", "resultFormat": "time_series", "orderByTime": "ASC", "tags": [ { "key": "hostname", "value": "server2", "operator": "=" } ], "groupBy": [], "select": [ [ { "type": "field", "params": [ "value" ] }, { "type": "count", "params": [] } ] ], "measurement": "cpu", "hide": false, "alias": "B" } ], "options": { "reduceOptions": { "values": false, "calcs": [ "lastNotNull" ], "fields": "" }, "orientation": "auto", "textMode": "auto", "colorMode": "value", "graphMode": "area", "justifyMode": "auto" }, "fieldConfig": { "defaults": { "mappings": [], "thresholds": { "mode": "absolute", "steps": [ { "value": null, "color": "green" }, { "value": 80, "color": "red" } ] }, "color": { "mode": "thresholds" }, "decimals": 2 }, "overrides": [] }, "datasource": { "uid": "000000002", "type": "influxdb" }, "pluginVersion": "9.1.3-e1f2f3c", "transformations": [ { "id": "calculateField", "options": { "mode": "binary", "reduce": { "reducer": "sum" }, "binary": { "operator": "/", "reducer": "sum", "left": "B", "right": "A" } } } ] }