enhance: [2.4] Add thread watcher to provide actual thread num (#37905)

[congqixia]

Cherry pick from master pr: #37905

Related to #37904

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[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: congqixia

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Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/milvus-io/milvus/blob/2.4/OWNERS)~~ [congqixia] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[congqixia]

wait until 2.4.17 released /hold

[mergify[bot]]

@congqixia E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 79.65%. Comparing base (e63a2f3) to head (528a0f8). Report is 3 commits behind head on 2.4.

Additional details and impacted files

[](https://app.codecov.io/gh/milvus-io/milvus/pull/37921?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=milvus-io) ```diff @@ Coverage Diff @@ ## 2.4 #37921 +/- ## ========================================== - Coverage 79.70% 79.65% -0.06% ========================================== Files 1069 1069 Lines 166979 166980 +1 ========================================== - Hits 133092 133004 -88 - Misses 29490 29553 +63 - Partials 4397 4423 +26 ``` | [Files with missing lines](https://app.codecov.io/gh/milvus-io/milvus/pull/37921?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=milvus-io) | Coverage Δ | | |---|---|---| | [pkg/metrics/info\_metrics.go](https://app.codecov.io/gh/milvus-io/milvus/pull/37921?src=pr&el=tree&filepath=pkg%2Fmetrics%2Finfo_metrics.go&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=milvus-io#diff-cGtnL21ldHJpY3MvaW5mb19tZXRyaWNzLmdv) | `100.00% <ø> (ø)` | | | [pkg/metrics/metrics.go](https://app.codecov.io/gh/milvus-io/milvus/pull/37921?src=pr&el=tree&filepath=pkg%2Fmetrics%2Fmetrics.go&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=milvus-io#diff-cGtnL21ldHJpY3MvbWV0cmljcy5nbw==) | `100.00% <100.00%> (ø)` | | ... and [35 files with indirect coverage changes](https://app.codecov.io/gh/milvus-io/milvus/pull/37921/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=milvus-io)

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🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests

[congqixia]

/run-cpu-e2e

[mergify[bot]]

@congqixia E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

[congqixia]

/run-cpu-e2e

[congqixia]

/unhold