Module mz_storage::metrics

Metrics for all things storage.

The structure of this module is designed to make adding new metrics as easy as possible. The structure and naming conventions are as follows:

Metrics for X end up in the x.rs submodule, unless X fits into one of the existing submodules. The struct XMetricsDefs defines the CounterVec/GaugeVec/etc’s that must be registered with the MetricsRegistry to create new metrics. XMetricsDefs should be a sub-field of StorageMetrics (or recursively a sub-field). XMetricsDefs has a register_with function to create it using a MetricsRegistry.

XMetrics contains the actual gauges/counters/etc that are created using XMetricsDefs. Typically these are created with new functions that takes a &XMetricsDefs, a GlobalId, and a worker id, but sometimes more complex schemes are used, for metrics that are globally shared, or have some other shape to their labels.

StorageMetrics is the main entry-point to this module, and for convenience, typically provides a get_x_metrics to obtain an XMetrics struct. This is to prevent users from needing to interact with metrics definitions into the code that actually bumps those metrics.

Modules

• decode
  Utilities for tracking metrics related to decoding.
• sink
  Metrics for sinks.
• source
  “Base” metrics used by all dataflow sources.
• upsert
  Metrics for upsert sources.

Structs

• StorageMetrics
  A top-level struct holding all various definitions of all metrics use by the mz-storage crate.