beast::insight::Event documents itself as carrying "a millisecond time, or
other integral value", but both backends assumed the first case: the OTel
bridge declared every instrument with unit `ms` and StatsD tagged every
sample `|ms`. One Event does not measure time -- ServerHandler's "size"
records the serialized RPC response length -- so it exported as
rpc_size_milliseconds and inherited the millisecond bucket ladder. A quarter
of its samples landed above that ladder's top edge, and since Prometheus
returns the second-highest edge for a quantile in the `+Inf` bucket, its p95
panel showed a flat 5.00 kB rather than a measurement.
Adds beast::insight::Unit (Millis, Bytes) plus otelUnitCode(), carried on
EventImpl and selectable at makeEvent(). Naming the unit at creation is what
lets a backend pick the export unit and, through it, the bucket ladder.
- Collector gains a virtual makeEvent(name, Unit) whose default delegates to
the millisecond overload, so a collector that cannot act on a unit keeps
working unchanged. NullCollector and the Groups wrapper override it.
- The Groups override matters most: call sites reach a collector through a
Group, so forwarding only the prefixed name would silently drop the unit.
A test covers that hop specifically.
- Event gains notify(std::uint64_t) for non-duration samples, replacing
ServerHandler's `Event::value_type{response.size()}` -- wrapping a byte
count in a std::chrono::milliseconds compiles but reads as a duration to
everything downstream.
- EventImpl::value_type stays std::chrono::milliseconds. Widening it would
change the wire value of every existing StatsD timer, and metrics needing
finer resolution use the OTel-native microsecond instruments.
The StatsD collector deliberately keeps emitting `|ms`: that path is retired
here (its UDP port is commented out of the compose file and the integration
test fails if anything listens on 8125), so changing its wire format would
alter a legacy contract with no consumer and no way to verify it.
The exported name does not change yet -- OTelEventImpl still hardcodes its
unit. That follows with the unit-keyed histogram views.
The bucket edges for the OTel histograms lived as file-local `namespace {}`
constants, unreachable from any test, and they drifted from the collector's
spanmetrics ladder they were specified to match. The millisecond ladder
stayed capped at 5 s after the collector side was extended to 30 s, so any
quantile above 5 s read back as a flat 5000 -- Prometheus returns the
second-highest edge for a quantile in the `+Inf` bucket, which looks like a
measurement rather than an error.
Adds include/xrpl/telemetry/HistogramBuckets.h as the single owner of the
ladders, with a constexpr validator plus static_asserts so a descending or
duplicated edge cannot compile, and gtest coverage that pins the floor and
ceiling against the measured distributions:
- kMillisecondBuckets carries every representable collector edge and extends
to 120 s, because the updatepaths job type averages ~60 s and a 30 s
ceiling would censor it exactly as 5 s does today. Sub-millisecond
collector edges are omitted: beast::insight::Event rounds durations up to
whole milliseconds, so they would collect nothing.
- kByteBuckets is new, for Events whose samples are sizes rather than
durations. Edges follow the measured RPC response distribution (mean
2131 B, half under 1 kB, tail mean bounded at 7538 B) rather than a guess,
so the resolution sits between 512 B and 64 kB.
No behaviour change yet -- nothing consumes the header until the views are
rewired.
clang-tidy runs misc-include-cleaner with WarningsAsErrors, so a symbol
reached only transitively fails CI. Add the direct includes for JLOG,
beast::Journal, StartUpType, TokenType, toBase58, std::exception and
std::size_t.
JLOG is defined in xrpl/basics/Log.h, and libxrpl.beast cannot include
xrpl.basics -- basics depends on beast, not the reverse. Use the journal
stream idiom the rest of the file already uses.
beast::insight instruments are created during ApplicationImp's member-init
list, and opentelemetry-cpp 1.28 never rebinds an already-vended Meter, so an
instrument created before the MeterProvider is published records nothing for
the rest of the process. Observable instruments carry the opposite constraint:
registering one arms the SDK reader thread, and its callbacks run hook handlers
that read services which do not exist that early.
Publish the provider in Telemetry's constructor, ahead of every producer, and
defer only the observables. Collector gains onCollectionReady() and
onCollectionStopping(); OTelCollector arms and disarms its gauges in response.
StatsDCollector starts its polling thread in its own constructor and had the
same hazard, so it uses the pair to gate that thread.
The metrics resource carries service.instance.id and is immutable once built,
so the node public key is resolved in Main.cpp, where a config error can still
be reported, and passed to makeApplication(). getNodeIdentity() remains
authoritative; both paths now share readNodeIdentity(), so telemetry cannot
report a key the node has abandoned.
An explicit ~ApplicationImp stops observing and stops telemetry, covering the
setup() failure paths that never reach run(). Telemetry::stop() is once-only
and no longer clears another instance's global pointer. The histogram view's
meter selector now matches the meter actually in use, so its bucket boundaries
apply for the first time.
makeTelemetrySetup() rejects a contradictory [telemetry] mutual-TLS
setup by throwing, but it is called from ApplicationImp's
member-initializer list. A try/catch in the constructor body cannot
reach a throw from there, and nothing further up the stack caught it
either, so a config mistake reached std::terminate: the default handler
printed a terminate dump and raised SIGABRT, leaving a core file
instead of a startup error.
Catch std::exception around makeApplication() in run(), report the
reason on stderr and return -1, so the failure is a clean non-zero exit
with a message an operator can act on. Only the construction is
wrapped. setup() starts subsystems whose shutdown order is delicate and
is left outside deliberately, because unwinding a half-started
Application would skip the normal stop sequence.
Gate both validation guards on enabled. A node with telemetry switched
off previously refused to start over certificate paths that nothing
would read.
Document both throws on makeTelemetrySetup(), state in
cfg/xrpld-example.cfg and the configuration reference that a partial
mutual-TLS setup is fatal and that the checks apply only when
enabled=1, and add a runbook troubleshooting entry keyed on the two
error messages.
Tests cover both guards with the message asserted so the two are told
apart, both enabled=0 paths, and the default plaintext configuration.
These comments pointed at a planning folder and at its rollout phase
numbering, neither of which is part of the shipped tree, so the
references would dangle for any reader of the repository. Each comment
now states the fact it was pointing at.
