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fix: decrement HashmapPidPageToMappingInfo metric on processPIDExit#79

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wehzzz merged 1 commit into
DataDog:datadogfrom
wehzzz:dd-fix-pid-page-to-mapping-metric
May 11, 2026
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fix: decrement HashmapPidPageToMappingInfo metric on processPIDExit#79
wehzzz merged 1 commit into
DataDog:datadogfrom
wehzzz:dd-fix-pid-page-to-mapping-metric

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@wehzzz wehzzz commented May 11, 2026

Summary

Recently, we observed some unusual behavior regarding the HashmapPidPageToMappingInfo metric.

image

According to the graph, we reached 163M entries in the eBPF map at one point, which seems way too high. When inspecting the actual map with:

$ bpftool -j map show id 31184 

{"id":11696,"type":"lpm_trie","name":"pid_page_to_map","flags":1,"bytes_key":16,"bytes_value":16,"max_entries":1048576,"bytes_memlock":2120920,"frozen":0,"btf_id":99410}

We are supposed to have a maximum of ~1M entries, so this value is definitely off.

Validating the changes

I tested by running both the unpatched and patched versions on separate nodes with identical workloads.

Without fix

image

With fix

image

…open-telemetry#1400)

Co-authored-by: Christos Kalkanis <christos.kalkanis@elastic.co>
@wehzzz wehzzz self-assigned this May 11, 2026
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wehzzz commented May 11, 2026

/merge

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gh-worker-devflow-routing-ef8351 Bot commented May 11, 2026

View all feedbacks in Devflow UI.

2026-05-11 11:39:12 UTC ℹ️ Start processing command /merge


2026-05-11 11:39:17 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in datadog is approximately 0s (p90).


2026-05-11 12:47:24 UTC ℹ️ MergeQueue: Retrying because an high priority merge request needed to be processed first. No action is needed from your side.


2026-05-11 12:47:28 UTC ⚠️ MergeQueue: This merge request build was cancelled

martin.levesque@datadoghq.com cancelled this merge request build

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wehzzz commented May 11, 2026

/merge -c

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gh-worker-devflow-routing-ef8351 Bot commented May 11, 2026

View all feedbacks in Devflow UI.

2026-05-11 12:47:15 UTC ℹ️ Start processing command /merge -c

@wehzzz wehzzz merged commit 7441a3f into DataDog:datadog May 11, 2026
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2 participants