Module metrics

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Available on crate feature metrics only.

Expand description

Metrics for materialize systems.

The idea here is that each subsystem keeps its metrics in a scoped-to-it struct, which gets registered (once) to the server’s (or a test’s) prometheus registry.

Instead of using prometheus’s (very verbose) metrics definitions, we rely on type inference to reduce the verbosity a little bit. A typical subsystem will look like the following:

#[derive(Debug, Clone)] // Note that prometheus metrics can safely be cloned
struct Metrics {
    pub bytes_sent: IntCounter,
}

impl Metrics {
    pub fn register_into(registry: &MetricsRegistry) -> Metrics {
        Metrics {
            bytes_sent: registry.register(metric!(
                name: "mz_pg_sent_bytes",
                help: "total number of bytes sent here",
            )),
        }
    }
}

Modules§

delete_on_drop 🔒: Support for metrics that get removed from their corresponding metrics vector when dropped.
raw: Access to non-delete-on-drop vector types

Structs§

ComputedGenericGauge: A Gauge whose value is computed whenever it is observed.
DeleteOnDropMetric: A Metric wrapper that deletes its labels from the vec when it is dropped.
DeleteOnDropWrapper: A wrapper for metrics to require delete on drop semantics
ExecTimeFuture: Future returned by MetricsFutureExt::exec_time.
Histogram: A Metric counts individual observations from an event or sample stream in configurable buckets. Similar to a Summary, it also provides a sum of observations and an observation count.
MakeCollectorOpts: Options for MakeCollector. This struct should be instantiated using the metric macro.
MetricsRegistry: The materialize metrics registry.
PrometheusOpts: A struct that bundles the options for creating most Metric types.
UnspecifiedMetric: A type level flag used to ensure callers specify the kind of metric to record for MetricsFutureExt.
WallTimeFuture: Future returned by MetricsFutureExt::wall_time.

Traits§

DurationMetric 🔒: A trait makes recording a duration generic over different prometheus metrics. This allows us to de-dupe the implemenation of Future for our wrapper Futures like WallTimeFuture and ExecTimeFuture over different kinds of prometheus metrics.
MakeCollector: A wrapper for creating prometheus metrics more conveniently.
MetricVecExt: Extension trait for metrics vectors.
MetricVec_: A trait that allows being generic over MetricVecs.
MetricsFutureExt: Exposes combinators that report metrics related to the execution of a Future to prometheus.
PromLabelsExt: An extension trait for types that are valid (or convertible into) prometheus labels: slices/vectors of strings, and BTreeMaps.

Functions§

register_runtime_metrics: Register the Tokio runtime’s metrics in our metrics registry.

Type Aliases§