# Prometheus

The `prometheus`

adapter collects Istio metrics and makes them available to Prometheus.

## Params

Configuration format for the `prometheus`

adapter.

## Params.MetricInfo

Describes how a metric should be represented in Prometheus.

## Params.MetricInfo.BucketsDefinition

Describes buckets for DISTRIBUTION kind metrics.

## Params.MetricInfo.BucketsDefinition.Explicit

Specifies a set of buckets with arbitrary widths.

There are `size(bounds) + 1`

(= `N`

) buckets. Bucket `i`

has the following boundaries:

- Upper bound (
`0 <= i < N-1`

):`bounds[i]`

- Lower bound (
`1 <= i < N`

):`bounds[i - 1]`

The `bounds`

field must contain at least one element. If `bounds`

has only one element, then there are no finite buckets, and that single element is the common boundary of the overflow and underflow buckets.

## Params.MetricInfo.BucketsDefinition.Exponential

Specifies an exponential sequence of buckets that have a width that is proportional to the value of the lower bound. Each bucket represents a constant relative uncertainty on a specific value in the bucket.

There are `num_finite_buckets + 2`

(= `N`

) buckets. The two additional buckets are the underflow and overflow buckets.

Bucket `i`

has the following boundaries:

- Upper bound (0 <= i < N-1):
`scale * (growth_factor ^ i)`

- Lower bound (1 <= i < N):
`scale * (growth_factor ^ (i - 1))`

## Params.MetricInfo.BucketsDefinition.Linear

Specifies a linear sequence of buckets that all have the same width (except overflow and underflow). Each bucket represents a constant absolute uncertainty on the specific value in the bucket.

There are `num_finite_buckets + 2`

(= `N`

) buckets. The two additional buckets are the underflow and overflow buckets.

Bucket `i`

has the following boundaries:

- Upper bound (
`0 <= i < N-1`

):`offset + (width * i)`

- Lower bound (
`1 <= i < N`

):`offset + (width * (i - 1))`

## Params.MetricInfo.Kind

Describes what kind of metric this is.

Name | Description |
---|---|

`UNSPECIFIED` | |

`GAUGE` | |

`COUNTER` | |

`DISTRIBUTION` |