chore(compat): MAX_PY=3.14 last-supported, wrap fail-closes at 3.16 (PROF-14439)

[vlad-scherbich]

Description

Delta vs #19906.

MAX_PY is (3, 14) — last officially supported, matching requires-python <3.15. NEXT_MAX_PY is (3, 15). wrap/lazy stay live on 3.15 and fail-close at 3.16, not at NEXT_MAX_PY. PY_315_VERSION_INFO is the CPython API floor and is not aliased to MAX_PY.

This PR does not widen requires-python.

Layer	Meaning	Which PR
Compiled into artifact	n/a	—
Armed at runtime	wrap() live on 3.15; fail-close at 3.16	this PR
Observable in product/Python	MAX_PY=3.14, NEXT_MAX_PY=3.15, PY_315 floor	this PR

Testing

Constants pin MAX_PY=(3, 14), NEXT_MAX_PY=(3, 15), PY_315=(3, 15). wrap() monkeypatch pins fail-close at 3.16.

Risks

None.

Additional Notes

Official do-not-merge line is #19995 ← #19996.

No release note: internal constants, changelog/no-changelog.

[cit-pr-commenter-54b7da]

Circular import analysis

⚠️ Existing circular imports

There are 3 circular imports that already exist on the base branch and have not been changed by this PR.

ddtrace.llmobs -> ddtrace.llmobs._evaluators -> ddtrace.llmobs._evaluators.format -> ddtrace.llmobs._experiment -> ddtrace.llmobs
ddtrace.errortracking._handled_exceptions.bytecode_injector -> ddtrace.errortracking._handled_exceptions.callbacks -> ddtrace.errortracking._handled_exceptions.collector -> ddtrace.errortracking._handled_exceptions.bytecode_reporting -> ddtrace.errortracking._handled_exceptions.bytecode_injector
ddtrace.appsec._asm_request_context -> ddtrace.appsec._iast._iast_request_context_base -> ddtrace.appsec._iast._iast_env -> ddtrace.appsec._iast.reporter -> ddtrace.appsec._exploit_prevention.stack_traces -> ddtrace.appsec._asm_request_context

[cit-pr-commenter-54b7da]

Dependency direction analysis

⚠️ Existing dependency direction violations

There are 230 dependency direction violations that already exist on the base branch and have not been changed by this PR.

Show existing violations (showing 5 of 230 highest severity)

ddtrace.internal.tracemethods -×-> ddtrace.trace  (internal-core -> product:tracing, score=134)
ddtrace.llmobs._integrations.pydantic_ai -×-> ddtrace.trace  (product:llmobs -> product:tracing, score=132)
ddtrace.llmobs._integrations.base -×-> ddtrace.trace  (product:llmobs -> product:tracing, score=132)
ddtrace.internal.opentelemetry.span -×-> ddtrace.trace  (product:opentelemetry -> product:tracing, score=132)
ddtrace.debugging._debugger -×-> ddtrace.trace  (product:debugging -> product:tracing, score=132)

To see all violations, download the layers-base.json and layers-pr.json artifacts from this CI job and run:

uv run --script scripts/import-analysis/layers.py compare layers-base.json layers-pr.json

[cit-pr-commenter-54b7da]

Codeowners resolved as

Resolved from the full PR diff against vlad/py315-riotfile using the target branch CODEOWNERS file.
CODEOWNERS team requests not listed below are not required by the current file set.

ddtrace/internal/bytecode_injection/__init__.py                         @DataDog/apm-core-python
ddtrace/internal/compat.py                                              @DataDog/python-guild @DataDog/apm-core-python
ddtrace/internal/coverage/instrumentation_py3_12.py                     @DataDog/ci-app-libraries
ddtrace/internal/lazy.py                                                @DataDog/apm-core-python
ddtrace/internal/monitoring.py                                          @DataDog/apm-core-python
ddtrace/internal/wrapping/__init__.py                                   @DataDog/apm-core-python
ddtrace/internal/wrapping/asyncs.py                                     @DataDog/apm-core-python
ddtrace/internal/wrapping/context.py                                    @DataDog/apm-core-python
ddtrace/internal/wrapping/generators.py                                 @DataDog/apm-core-python
tests/internal/test_py315_import_degrade.py                             @DataDog/apm-core-python

[pr-commenter]

Benchmarks

Benchmark execution time: 2026-09-02 20:47:37

Comparing candidate commit 5b7eaa7 in PR branch vlad/py315-current-py-version with baseline commit 1b2e241 in branch main.

📊 Benchmarking dashboard

Found 0 performance improvements and 7 performance regressions! Performance is the same for 575 metrics, 10 unstable metrics, 2 known flaky benchmarks, 16 flaky benchmarks without significant changes.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

• 🟩 = significantly better candidate vs. baseline
• 🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

scenario:httppropagationextract-tracecontext_headers

• 🟥 execution_time [+2.331µs; +2.580µs] or [+7.237%; +8.010%]

scenario:httppropagationinject-ids_only

• 🟥 execution_time [+2.409µs; +2.613µs] or [+14.460%; +15.689%]

scenario:iastaspects-rstrip_aspect

• 🟥 execution_time [+72.512µs; +81.563µs] or [+19.230%; +21.631%]

scenario:iastaspectsospath-ospathbasename_aspect

• 🟥 execution_time [+109.970µs; +117.818µs] or [+27.788%; +29.771%]

scenario:otelspan-start

• 🟥 execution_time [+2.314ms; +3.329ms] or [+7.344%; +10.564%]

scenario:telemetryaddmetric-1-count-metric-1-times

• 🟥 execution_time [+564.637ns; +611.219ns] or [+20.853%; +22.573%]

scenario:tracer-small

• 🟥 execution_time [+41.565µs; +43.295µs] or [+12.822%; +13.356%]

Unstable benchmarks

These benchmarks have a confidence interval too wide to call a change; treat them as noise rather than signal.

scenario:coreapiscenario-context_with_data_listeners

• unstable execution_time [-705.033ns; +784.762ns] or [-6.360%; +7.079%]

scenario:coreapiscenario-core_dispatch_1_listener

• unstable execution_time [-33.955ns; +31.430ns] or [-5.561%; +5.148%]

scenario:coreapiscenario-core_dispatch_50_listeners

• unstable execution_time [-1661.794ns; +1621.519ns] or [-9.808%; +9.570%]

scenario:coreapiscenario-core_dispatch_exception_listeners

• unstable execution_time [-1258.799ns; +1206.943ns] or [-9.693%; +9.294%]

scenario:coreapiscenario-core_dispatch_listeners

• unstable execution_time [-319.779ns; +328.369ns] or [-8.775%; +9.011%]

scenario:coreapiscenario-core_dispatch_no_args_listeners

• unstable execution_time [-252.746ns; +253.651ns] or [-8.706%; +8.737%]

scenario:coreapiscenario-core_dispatch_with_results_1_listener

• unstable execution_time [-80.051ns; +66.856ns] or [-7.062%; +5.898%]

scenario:coreapiscenario-core_dispatch_with_results_50_listeners

• unstable execution_time [-3957.000ns; +4054.918ns] or [-9.654%; +9.893%]

scenario:coreapiscenario-core_dispatch_with_results_listeners

• unstable execution_time [-813.024ns; +740.543ns] or [-10.046%; +9.151%]

scenario:packagesupdateimporteddependencies-import_many_stdlib_cached

• unstable execution_time [-54708.486ns; +54717.606ns] or [-9.512%; +9.514%]

Known flaky benchmarks

These benchmarks are marked as flaky and will not trigger a failure. Modify FLAKY_BENCHMARKS_REGEX to control which benchmarks are marked as flaky.

scenario:iastaspects-swapcase_aspect

• 🟥 execution_time [+37.111µs; +43.814µs] or [+13.299%; +15.701%]

scenario:span-start

• 🟥 execution_time [+1.796ms; +1.969ms] or [+12.946%; +14.192%]

Known flaky benchmarks without significant changes:

• scenario:errortrackingflasksqli-baseline
• scenario:flasksimple-iast-get
• scenario:iastaspects-casefold_aspect
• scenario:iastaspects-casefold_noaspect
• scenario:iastaspects-index_aspect
• scenario:iastaspects-ljust_noaspect
• scenario:iastaspects-lower_aspect
• scenario:iastaspects-replace_aspect
• scenario:iastaspects-title_noaspect
• scenario:iastaspects-translate_aspect
• scenario:iastaspects-translate_noaspect
• scenario:iastaspects-upper_noaspect
• scenario:packagespackageforrootmodulemapping-cache_off
• scenario:packagespackageforrootmodulemapping-cache_on
• scenario:sethttpmeta-all-enabled
• scenario:telemetryaddmetric-record-100-metrics

[datadog-prod-us1-6]

 

⚠️ Warnings

❌ Your PR has failed checks. Please review the issues below and take necessary action before merging.

🚦 5 Pipeline jobs failed

DataDog/apm-reliability/dd-trace-py | contrib/gunicorn 5/6 — 🔄 Retry may pass, looks flaky

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DataDog/apm-reliability/dd-trace-py | contrib/loguru 1/1 — 🔄 Retry may pass, looks flaky

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DataDog/apm-reliability/dd-trace-py | contrib/mariadb 5/7

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View all 5 failed jobs.

ℹ️ Info

No other issues found (see more)

🧪 All tests passed
❄️ No new flaky tests detected

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[Copilot]

Pull request overview

This PR standardizes Python version bound constants in ddtrace.internal.compat by introducing MAX_PY_VERSION / NEXT_MAX_PY_VERSION and derived predicates (PY_GTE_MAX, PY_GTE_NEXT_MAX), then updates internal call sites and tests to use these shared checks (including wrapping fail-closed behavior and injection runtime allow-listing).

Changes:

• Add MAX/NEXT_MAX version constants + predicates to ddtrace.internal.compat.
• Replace ad-hoc version comparisons with shared predicates in wrapping-related code paths and tests.
• Align injection bootstrap runtime allow-list upper bound with NEXT_MAX_PY_VERSION_INFO.

Reviewed changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
ddtrace/internal/compat.py	Adds MAX/NEXT_MAX constants and PY_GTE_* predicates (with updated exports).
ddtrace/internal/wrapping/__init__.py	Switches wrap/wrap_bytecode fail-closed gate to PY_GTE_MAX.
ddtrace/internal/wrapping/context.py	Switches the 3.16+ fail-closed import-time gate to PY_GTE_NEXT_MAX.
ddtrace/internal/module.py	Updates lazy-module behavior gating to PY_GTE_MAX.
ddtrace/internal/monitoring.py	Replaces 3.15+ import guard with a MAX-based guard/message.
ddtrace/internal/coverage/instrumentation_py3_12.py	Replaces hardcoded 3.15 boundaries with MAX_PY_VERSION_INFO for PEP 810-related behavior.
lib-injection/sources/sitecustomize.py	Sets injection runtime exclusive upper bound to (3, 16) via NEXT_MAX_PY_VERSION_INFO.
tests/internal/test_py315_import_degrade.py	Adds assertions for the new constants/predicates and updates skipifs to use PY_GTE_MAX.

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