PYTHON-5963 Only attach a shared operation id to retry attempts when APM/logging is enabled - #2960
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…APM/logging is enabled
NoahStapp
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Pull request overview
This PR addresses a performance regression introduced by always generating a stable “operation id” for retry attempts, even when command monitoring (APM) and structured logging are both disabled. It makes operation-id generation conditional on observability being enabled, while keeping the “shared operation id across retries” behavior when APM/logging is active.
Changes:
- Conditionally generate and attach a shared operation id for retry attempts only when command monitoring listeners are enabled or command/server-selection structured logging is enabled.
- Skip the
_op_id._OpIdContextoverhead entirely when no operation id is present. - Add sync + async regression tests asserting that no operation id is generated/propagated when neither APM nor logging is enabled.
Reviewed changes
Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.
Show a summary per file
| File | Description |
|---|---|
pymongo/asynchronous/mongo_client.py |
Only generate/use a shared operation id for retries when APM/logging is enabled (async path). |
pymongo/synchronous/mongo_client.py |
Same conditional operation-id behavior for the synchronous client. |
test/asynchronous/test_operation_id_retry.py |
Adds async test ensuring retries do not generate/attach an operation id when observability is off. |
test/test_operation_id_retry.py |
Adds sync equivalent of the “no APM/logging => no operation id” regression test. |
pymongo/_op_id.py |
Updates internal docstring to reflect the new conditional behavior. |
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| # Make sure APM and logging are disabled | ||
| for logger in (_COMMAND_LOGGER, _SERVER_SELECTION_LOGGER): | ||
| self.assertFalse(logger.isEnabledFor(logging.DEBUG)) | ||
| self.assertFalse(client._event_listeners.enabled_for_commands) | ||
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| # Make sure APM and logging are disabled | ||
| for logger in (_COMMAND_LOGGER, _SERVER_SELECTION_LOGGER): | ||
| self.assertFalse(logger.isEnabledFor(logging.DEBUG)) | ||
| self.assertFalse(client._event_listeners.enabled_for_commands) | ||
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| """Internal helpers for the APM operation id. | ||
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| The retryable read/write logic sets OP_ID for the duration of each attempt so | ||
| The retryable read/write logic sets OP_ID if APM/logging is enabled for the duration of each attempt so | ||
| that every attempt of one logical operation publishes the same operation_id. | ||
| Commands run outside that scope (handshake, auth, killCursors, pinned-cursor |
sleepyStick
approved these changes
Jul 24, 2026
Codecov Report✅ All modified and coverable lines are covered by tests. 📢 Thoughts on this report? Let us know! |
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|
Test failures are all known and unrelated. |
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PYTHON-5963
Changes in this PR
PYTHON-5903 ensured that all retry attempts share a single operation id. However, it does so even if there is no active event listener or logger, causing a ~5-10% performance regression due to extra overhead on very fast operations such as pings.
Test Plan
Added a new test to verify correct behavior.
Checklist
Checklist for Author
[ ] Did you update the changelog (if necessary)?[ ] Is any followup work tracked in a JIRA ticket? If so, add link(s).Checklist for Reviewer