Crate re_perf_telemetry 

Everything needed to set up telemetry (logs, traces, metrics) for both clients and servers.

Despite the name re_perf_telemetry, this actually handles all forms of telemetry, including all log output.

This sort of telemetry is always disabled on our OSS binaries, and is only used for

• The Rerun Hub infrastructure
• Profiling by Rerun developer

Logging strategy

• All our logs go through the structured tracing macros.

• We always log from tracing directly into stdio: we never involve the OpenTelemetry logging API. Production is expected to read the logs from the pod’s output. There is never any internal buffering going on, besides the buffering of stdio itself.

• All logs that happen as part of the larger trace/span will automatically be uploaded with that trace/span. This makes our traces a very powerful debugging tool, in addition to a profiler.

Tracing strategy

• All our traces go through the structured tracing macros. We never use the OpenTelemetry macros.

• The traces go through a first layer of filtering based on the value of RUST_TRACE, which functions similarly to a RUST_LOG filter.

• The traces are then sent to the OpenTelemetry SDK, where they will go through a pass of sampling before being sent to the OTLP endpoint. The sampling mechanism is controlled by the official OTEL environment variables.

• Spans that contains error logs will properly be marked as failed, and easily findable.

Metric strategy

• Our metric strategy is basically the opposite of our logging strategy: everything goes through OpenTelemetry directly, tracing is never involved.

• Metrics are uploaded (as opposed to scrapped!) using the OTLP protocol, on a fixed interval defined by the OTEL_METRIC_EXPORT_INTERVAL environment variable.

Modules

external

Structs

ClientOnResponse

Implements a tower_http::trace::OnResponse middleware for the gRPC client.

GrpcMakeSpan

Implements tower_http::trace::MakeSpan where the trace name is the gRPC method name.

GrpcOnEos

Implements a tower_http::trace::OnEos middleware.

GrpcOnFirstBodyChunk

Implements a tower_http::trace::OnBodyChunk middleware, but only accounts for the first one.

GrpcOnRequest

Implements a tower_http::trace::OnRequest middleware.

GrpcOnResponse

Implements a tower_http::trace::OnResponse middleware.

GrpcOnResponseOptions

RerunTracingSessionId

A validated rerun session id.

SpanMetadataCleanupLayer

A tracing_subscriber::Layer that cleans up SpanMetadata entries when spans close.

Telemetry

The Redap telemetry pipeline.

TelemetryArgs

Complete configuration for all things telemetry.

TelemetryLayerOptions

TraceHeaders

TracingInjectorInterceptor

This implements a tonic::service::Interceptor that injects trace/span metadata into the request headers, according to W3C standards.

Enums

LogFormat

TelemetryDropBehavior

Constants

RERUN_SESSION_TRACESTATE_KEY

The W3C tracestate key under which the rerun session id propagates.

Traits

EnvFilterExt

Functions

current_rerun_session_id

Returns the active rerun session id, if any.

current_trace_headers

Export the active trace in the current context as the W3C trace headers, if any.

current_trace_id

Returns the active TraceId in the current context, if any.

dec_active_tracing_session_count

Decrement the active-session counter. Called by Python tracing_session().__exit__; the Rust with_tracing_session path goes through ActiveSessionGuard’s drop instead.

inc_active_tracing_session_count

Increment the active-session counter. Called by Python tracing_session().__enter__; the Rust with_tracing_session path goes through ActiveSessionGuard instead.

is_telemetry_active

Returns true once Telemetry::init has run with telemetry enabled (i.e. the tracing subscriber, OTLP exporters, and global propagator are installed).

new_client_telemetry_layer

Creates a new tower::Layer middleware that automatically:

new_server_telemetry_layer

Creates a new tower::Layer middleware that automatically:

to_short_str

Displays a possibly long list of items to a length limited list of items.

with_current_tracing_session

Wrap f so the active rerun session id is resolved once at entry (via the registered [SessionIdReader]) and stays accessible to every outbound gRPC inside it without re-invoking the reader.

with_tracing_session

Tag every Rerun Hub request inside f with a fresh session id, so the full set of requests can be correlated end-to-end for support.

Type Aliases

ClientTelemetryLayer

ServerTelemetryLayer