Document enabling query metrics for self-hosted MongoDB 8.0 - #39441
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Add a Query Metrics section to the self-hosted MongoDB DBM setup page explaining that query stats collection is disabled by default and must be enabled via the internalQueryStatsSampleRate server parameter, with config file, command line, and runtime setParameter examples.
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August 24, 2026 21:23
dalextorres
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The command-line example configures only mongod. A sharded deployment also needs the parameter on each mongos process.
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| Or pass it on the command line: | ||
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| {{< code-block lang="shell" >}} | ||
| mongod --setParameter internalQueryStatsSampleRate=1.0 |
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Users can leave query statistics off on mongos and miss query metrics for router traffic.
Assertion details
- Input: A user enables query metrics from the command line for a
mongosprocess in a sharded cluster. - Expected:
The command-line option must show both server types or use a binary placeholder. - Actual: The command example starts
mongodonly. It gives no command formongos.
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What does this PR do? What is the motivation?
Adds a Query Metrics section to the self-hosted MongoDB DBM setup page explaining that query metrics for self-hosted MongoDB require MongoDB 8.0+ and that query stats collection is disabled by default on the server.
The mongo DBM integration's query metrics feature reads via the
$queryStatsaggregation pipeline, but the integration cannot enable collection itself — users must set theinternalQueryStatsSampleRateserver parameter on eachmongod/mongos. Without this section, self-hosted MongoDB 8.0 users would not know they need to enable a server parameter to get query metrics.The section shows the three ways to set the parameter (config file, command line, and runtime
setParameter), notes that the runtime form is not persistent, and links to the MongoDB Query Stats server-parameters documentation.Merge instructions
Merge readiness:
AI assistance
Used Claude Code for research (MongoDB
$queryStatsserver parameter behavior) and initial draft of the doc section; manually reviewed and adjusted.Additional notes
The
internalQueryStatsSampleRate=1.0value (100% sampling) matches what was validated in the DBM agent integration environment. Users can lower the value to reduce overhead.