chore: simplify periodic thread implementation

[P403n1x87]

Description

We simplify the implementation of native periodic threads by removing unnecessary defensive coding. The changes in #18921 provided the minimal fix required to fix a fork-related hang, with the defensive coding in #18636 and #18920 thus becoming redundant.

[cit-pr-commenter-54b7da]

Codeowners resolved as

ddtrace/internal/_threads.cpp                                           @DataDog/apm-core-python
ddtrace/internal/threads.py                                             @DataDog/apm-core-python

[cit-pr-commenter-54b7da]

Circular import analysis

⚠️ Existing circular imports

There are 45 circular imports that already exist on the base branch and have not been changed by this PR.

Show existing cycles (showing 5 of 45 shortest)

ddtrace.internal.core -> ddtrace._trace.span -> ddtrace.internal.core
ddtrace.internal.datastreams -> ddtrace.internal.datastreams.kombu -> ddtrace.internal.datastreams
ddtrace.internal.datastreams -> ddtrace.internal.datastreams.aiokafka -> ddtrace.internal.datastreams
ddtrace.internal.datastreams -> ddtrace.internal.datastreams.botocore -> ddtrace.internal.datastreams
ddtrace.internal.datastreams -> ddtrace.internal.datastreams.google_cloud_pubsub -> ddtrace.internal.datastreams

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

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

[pr-commenter]

Benchmarks

Benchmark execution time: 2026-07-17 15:53:04

Comparing candidate commit ba3350b in PR branch chore/simplfy-threads with baseline commit dc8538c in branch main.

Found 0 performance improvements and 5 performance regressions! Performance is the same for 612 metrics, 10 unstable metrics.

scenario:iastaspects-lstrip_aspect

• 🟥 execution_time [+64.857µs; +72.774µs] or [+19.794%; +22.211%]

scenario:iastaspects-swapcase_aspect

• 🟥 execution_time [+67.799µs; +76.998µs] or [+19.327%; +21.949%]

scenario:iastaspectsospath-ospathbasename_aspect

• 🟥 execution_time [+108.152µs; +114.700µs] or [+24.826%; +26.329%]

scenario:span-start

• 🟥 execution_time [+1.149ms; +1.311ms] or [+7.267%; +8.293%]

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

• 🟥 execution_time [+178.374ns; +214.702ns] or [+8.551%; +10.292%]

[datadog-official]

 

⚠️ Warnings

🚦 74 Pipeline jobs failed

DataDog/apm-reliability/dd-trace-py | build linux serverless: [amd64, cp315-cp315, v113741238-d2b8243-manylinux2014_x86_64, 1]     

DataDog/apm-reliability/dd-trace-py | build linux serverless: [arm64, cp315-cp315, v113741357-d2b8243-manylinux2014_aarch64, 1]     

DataDog/apm-reliability/dd-trace-py | build linux serverless: [arm64, cp315-cp315, v113741589-d2b8243-musllinux_1_2_aarch64, 1]     

View all 74 failed jobs.

ℹ️ Info

No other issues found (see more)

🧪 All tests passed
❄️ No new flaky tests detected

Useful? React with 👍 / 👎

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: ba3350b | Docs | Datadog PR Page | Give us feedback!}

[brettlangdon]

this is still the same bug as before, no?

or the issue was one of the "remove from periodic thread" calls below that was deleted?

[P403n1x87]

yes it was the one deleted in #18921