The table of contents in this file indexes third- and fourth-level headings,
so a new subsection that is absent from it is a gap rather than a style
choice.
mutable_ on a protobuf optional submessage allocates it and sets its has-bit
at the call site, before the helper can decide there is nothing to write. A
caller that dereferences it ships an empty TraceContext whenever nothing is
recorded, and its peers each take a branch to extract nothing.
Document the rule with the right and wrong forms side by side.
The conditional-compilation section promised zero overhead when telemetry is
not wanted. The span disappears, but the arguments passed to it do not: the
compiled-out guards are ordinary inline functions, so a to_string() or a hash
in an argument list still runs and its result is then discarded.
State that, show the guard that does remove the work, and name the opposite
case -- the metric macros, which discard their arguments and need no guard.
detached() strips the thread-local OTel Scope so a guard can be safely
moved to and destroyed on another thread; it pops the Scope on the origin
thread and moves the span into a scope-less guard. rootSpan() starts a span
as a fresh trace root (kIsRootSpanKey) so inbound entry points never inherit
an ambient span left active on the thread.
Impl now holds an optional<Scope> (nullopt for detached guards). Updated the
SpanGuard class docs and docs/build/telemetry.md with the cross-thread rules.
The unit test lands on phase2 where the telemetry test module exists.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Flip the tracePeer Setup default and the trace_peer config parser
default from off to on, and update the example config and build doc to
match. Peer spans record only peer_id (a node-local numeric connection
id) plus trust/ledger metadata — no IP addresses or public keys — so
the privacy concern behind disabling it does not apply. The high-volume
characteristic is retained in the docs.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Replace references to non-existent TracingInstrumentation.h with
SpanGuard.cpp pimpl implementation that actually exists on this branch.
Update conditional compilation section to describe the pimpl approach.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Add span discard mechanism that drops unwanted spans before they enter
the batch export queue, saving both network bandwidth and storage.
FilteringSpanProcessor is a custom SpanProcessor decorator that wraps
BatchSpanProcessor. SpanGuard::discard() sets a thread-local flag
(tl_discardCurrentSpan) before calling Span::End(). The OTel SDK calls
OnEnd() synchronously on the same thread, where the flag is checked and
cleared to drop the span.
New file: DiscardFlag.h — zero-dependency header for the thread-local
flag, avoiding transitive include bloat from Telemetry.h.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Tempo is now the sole trace backend. Remove Jaeger all-in-one service
from docker-compose, otlp/jaeger exporter from OTel Collector config,
and Jaeger Grafana datasource provisioning file.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This change moves the sanitizer runtime options out to dedicated files, such that they can be used in multiple places (CI, local runs) without any need to rewrite them.