feat(trace-utils)!: change buffer implementation#2055
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| let num: u32 = self.change_buffer.read_unchecked(index); | ||
| self.string_table | ||
| .get_unchecked(num as usize) | ||
| .clone() | ||
| .unwrap_unchecked() |
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When a cached non-create operation such as SetName or SetServiceName is decoded from the shared FFI buffer, the caller reaches this helper without validating either that the string id is still present in string_table or that the argument bytes are in bounds. An out-of-sync/evicted string id that used to produce ChangeBufferError::StringNotFound now hits unwrap_unchecked(), which is undefined behavior across the FFI-facing change-buffer path rather than a recoverable error.
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Codecov Report❌ Patch coverage is Additional details and impacted files@@ Coverage Diff @@
## yannham/change-buffer-foundation #2055 +/- ##
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I'm converting back to draft in order to take a closer look at unsafe code/unbound reads and see if we can avoid them. |
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Add the main ChangeBufferState<T> struct and its full implementation: span creation/pooling, change buffer interpretation (opcodes), deferred tag resolution, span header materialization, flush logic, and string table management. This is the core state machine that processes batched span mutations from JS/WASM via a shared memory buffer. Co-Authored-By: Claude Opus 4.6 <[email protected]>
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There are a few issues with this implementation across the board which would be a bit difficult to explain so I just opened a PR on top of this PR instead: #2105
Feel free to reimplement based on the summary if that's easier, I thought it would be a smaller change when I started on it 😅
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@rochdev would that be ok to just merge this one first (after addressing reviews) and then proceed with your PR? I don't expect to do a lot of modifications and the code isn't used anywhere yet anyway. That'll just make for an easier review experience. If yes, please lift the request for changes. |
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…ibdd-data-pipeline, libdd-li... (#2201) # Release proposal for libdd-capabilities-impl, libdd-common, libdd-data-pipeline, libdd-library-config, libdd-remote-config, libdd-sampling, libdd-telemetry, libdd-tinybytes, libdd-trace-utils and their dependencies This PR contains version bumps based on public API changes and commits since last release. ## libdd-capabilities **Next version:** `2.1.0` **Semver bump:** `minor` **Tag:** `libdd-capabilities-v2.1.0` ### Commits - feat(data-pipeline)!: add stdout log trace exporter (#2074) ## libdd-common **Next version:** `5.1.0` **Semver bump:** `minor` **Tag:** `libdd-common-v5.1.0` ### Commits - refactor(clippy): prefer core and alloc imports (#2196) - fix: update rustls-webpki to 0.103.13 (#2187) - fix: update anyhow for unsoundness (#2186) - feat(machine id): Add helpers in ddcommon to fetch the machine UUID l… (#2163) ## libdd-ddsketch **Next version:** `1.1.0` **Semver bump:** `minor` **Tag:** `libdd-ddsketch-v1.1.0` ### Commits - feat(data-pipeline)!: export client-computed span stats as OTLP trace metrics (#2067) - test(ddsketch): add microbenchmarks for add/encode/collapse (#2125) ## libdd-trace-protobuf **Next version:** `4.0.0` **Semver bump:** `major` **Tag:** `libdd-trace-protobuf-v4.0.0` ### Commits - chore!: update protobufs to be in sync with datadog-agent (#2180) - feat(stats)!: add whole key cardinality limit (#2158) - feat(remote-config)!: use the proto file from the agent (#2165) - feat(data-pipeline): OTLP HTTP/protobuf trace export (#2115) ## libdd-capabilities-impl **Next version:** `3.0.0` **Semver bump:** `major` **Tag:** `libdd-capabilities-impl-v3.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.1.0 → ^5.1.0 ### Commits - feat(data-pipeline)!: add stdout log trace exporter (#2074) ## libdd-library-config **Next version:** `3.0.0` **Semver bump:** `major` **Tag:** `libdd-library-config-v3.0.0` ###⚠️ major bump forced due to: - `libdd-trace-protobuf`: ^3.0.2 → ^4.0.0 ### Commits - refactor(clippy): prefer core and alloc imports (#2196) - feat(library-config)!: caller-supplied threadlocal schema and extra process-context attributes (#2162) - fix(otel-thread-ctx): put the threadlocal attributes at the right place in the context (#2167) ## libdd-remote-config **Next version:** `2.0.0` **Semver bump:** `major` **Tag:** `libdd-remote-config-v2.0.0` ###⚠️ major bump forced due to: - `libdd-trace-protobuf`: ^3.0.2 → ^4.0.0 ### Commits - refactor(libdd-remote-config)!: hide Target inner properties so they are not leaked (#2182) - feat(remote-config)!: use the proto file from the agent (#2165) - refactor(rc): reexport Endpoint and Tag common types (#2147) ## libdd-trace-normalization **Next version:** `3.0.0` **Semver bump:** `major` **Tag:** `libdd-trace-normalization-v3.0.0` ###⚠️ major bump forced due to: - `libdd-trace-protobuf`: ^3.0.1 → ^4.0.0 ### Commits - feat(data-pipeline)!: CSS Trace Filters (#1985) ## libdd-shared-runtime **Next version:** `2.0.0` **Semver bump:** `major` **Tag:** `libdd-shared-runtime-v2.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.1.0 → ^5.1.0 ### Commits - feat(shared-runtime)!: SharedRuntime Borrowed & Owned mode (#2061) - feat(shared-runtime)!: use weak waker in trigger [APMSP-3371] (#2050) ## libdd-trace-utils **Next version:** `9.0.0` **Semver bump:** `major` **Tag:** `libdd-trace-utils-v9.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.2.0 → ^5.1.0 - `libdd-trace-protobuf`: ^3.0.2 → ^4.0.0 ### Commits - ci(miri): skip slow miri tests (#2188) - chore!: update protobufs to be in sync with datadog-agent (#2180) - feat(data-pipeline): add agentless export (#2081) - feat(data-pipeline)!: add stdout log trace exporter (#2074) - feat(data-pipeline): OTLP HTTP/protobuf trace export (#2115) - feat(otlp)!: Export OTLP spans with attribute-level OTel compatibility (#2091) - test(trace-utils): add V05 msgpack decode microbenchmark (#2127) - feat(data-pipeline)!: export client-computed span stats as OTLP trace metrics (#2067) - test(trace-utils): add VecMap microbenchmarks (#2126) - chore(stats)!: submit p0 telemetry in stats (#2130) - refactor(change-buffer)!: replace slot index with span_id, fix segment isolation (#2105) - feat(data-pipeline)!: CSS Trace Filters (#1985) - feat(trace-exporter): add v1 span and its encoder (#2039) - fix(trace-utils): mark decoded span maps as deduped (#2110) - feat(trace-utils)!: change buffer implementation (#2055) - feat(native-spans)!: change buffer foundation (#2046) - refactor(span)!: use VecMap for `meta`, `metrics` and `meta_struct` for v04 spans (#2043) - test: fix timeouts on heavily contended scenarios (#2093) ## libdd-telemetry **Next version:** `6.0.0` **Semver bump:** `major` **Tag:** `libdd-telemetry-v6.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.2.0 → ^5.1.0 - `libdd-shared-runtime`: ^1.0.0 → ^2.0.0 ### Commits - ci(miri): skip slow miri tests (#2188) - refactor(libdd-telemetry)!: avoid leaking libdd-common types in the public API (#2152) - feat(shared-runtime)!: SharedRuntime Borrowed & Owned mode (#2061) ## libdd-trace-obfuscation **Next version:** `5.0.0` **Semver bump:** `major` **Tag:** `libdd-trace-obfuscation-v5.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.2.0 → ^5.1.0 - `libdd-trace-protobuf`: ^3.0.2 → ^4.0.0 - `libdd-trace-utils`: ^8.0.0 → ^9.0.0 ### Commits - refactor(clippy): prefer core and alloc imports (#2196) - ci(miri): skip slow miri tests (#2188) - fix: update anyhow for unsoundness (#2186) ## libdd-trace-stats **Next version:** `6.0.0` **Semver bump:** `major` **Tag:** `libdd-trace-stats-v6.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.2.0 → ^5.1.0 - `libdd-shared-runtime`: ^1.0.0 → ^2.0.0 - `libdd-trace-protobuf`: ^3.0.2 → ^4.0.0 - `libdd-trace-utils`: ^8.0.0 → ^9.0.0 ### Commits - chore!: update protobufs to be in sync with datadog-agent (#2180) - feat(stats)!: send telemetry for cardinality limits (#2159) - feat(stats)!: add whole key cardinality limit (#2158) - fix(trace-stats)!: add grpc_method to aggregation key (#2151) - feat(shared-runtime)!: SharedRuntime Borrowed & Owned mode (#2061) - feat(data-pipeline)!: export client-computed span stats as OTLP trace metrics (#2067) - refactor(span)!: use VecMap for `meta`, `metrics` and `meta_struct` for v04 spans (#2043) ## libdd-data-pipeline **Next version:** `7.0.0` **Semver bump:** `major` **Tag:** `libdd-data-pipeline-v7.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.2.0 → ^5.1.0 - `libdd-shared-runtime`: ^1.0.0 → ^2.0.0 - `libdd-telemetry`: ^5.0.1 → ^6.0.0 - `libdd-trace-protobuf`: ^3.0.2 → ^4.0.0 - `libdd-trace-stats`: ^5.0.0 → ^6.0.0 - `libdd-trace-utils`: ^8.0.0 → ^9.0.0 ### Commits - feat(trace_exporter): enable telemetry in stats exporter (#2160) - refactor(libdd-telemetry)!: avoid leaking libdd-common types in the public API (#2152) - feat(stats): emit canonical gRPC status name for OTLP rpc.response.status_code (#2183) - feat(data-pipeline): add agentless export (#2081) - feat(stats)!: send telemetry for cardinality limits (#2159) - feat(stats)!: add whole key cardinality limit (#2158) - fix(trace-stats)!: add grpc_method to aggregation key (#2151) - feat(data-pipeline)!: add stdout log trace exporter (#2074) - feat(shared-runtime)!: SharedRuntime Borrowed & Owned mode (#2061) - feat(data-pipeline): OTLP HTTP/protobuf trace export (#2115) - feat(otlp)!: Export OTLP spans with attribute-level OTel compatibility (#2091) - feat(data-pipeline)!: export client-computed span stats as OTLP trace metrics (#2067) - chore(stats)!: submit p0 telemetry in stats (#2130) - feat(data-pipeline)!: CSS Trace Filters (#1985) - feat(shared-runtime)!: use weak waker in trigger [APMSP-3371] (#2050) - refactor(span)!: use VecMap for `meta`, `metrics` and `meta_struct` for v04 spans (#2043) - feat(stats)!: add endpoint gating to client-side stats [APMSP-3361] (#2040) ## libdd-dogstatsd-client **Next version:** `4.0.0` **Semver bump:** `major` **Tag:** `libdd-dogstatsd-client-v4.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.1.0 → ^5.1.0 ## libdd-sampling **Next version:** `5.0.0` **Semver bump:** `major` **Tag:** `libdd-sampling-v5.0.0` ###⚠️ major bump forced due to: - `libdd-common`: ^4.2.0 → ^5.1.0 - `libdd-trace-utils`: ^8.0.0 → ^9.0.0 [APMSP-3371]: https://datadoghq.atlassian.net/browse/APMSP-3371?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ --------- Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com> Co-authored-by: iunanua <[email protected]>
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What does this PR do?
This PR backports the change buffer implementation required for dd-trace-js adoption of native spans. Follow-up of #2046.
The change buffer is a contiguous region of memory where span operations are encoded from the JS runtime, similar to a byte code. The implementation decode all those span events and reconstruct the corresponding span objects.
Motivation
Required to land native spans dd-trace-js.
How to test the change?
tests included.