Efficiently store multiple metrics in a single series

Question

Is it efficient to store multiple metrics in a single series? There is support for multiple columns, but it seems that at least based on the 0.9 documentation that there is a preference towards a single series per metric and a column for value.

What I'm looking at is a way to store some related data (such as hd free, used, total) and having 3 separate series seems like a pain and would most certainly complicate queries that need to be made across the series.

Are there some general best practices for storing metrics such as these?

Answer 1

InfluxDB 0.9 will happily support up to 255 fields per series. The examples in the docs mostly have single field examples with a field key of "value" but there's nothing preventing you from having multiple fields. Since fields aren't indexed it should have no performance impact at all.

For example, here's a point with three field values:

{
    "database": "mydb",
    "points": [
         {
            "measurement": "disk",
            "tags": {
                "host": "server01",
                "type": "SSD"
            },
            "time": "2009-11-10T23:00:00Z",
            "fields": {
                "free": 318465464,
                "used": 682324110,
                "total": 1000789574
            }
        }
    ]
}