[exporter/prometheus_remote_writeexporter] Fix WAL buffered data stall …

[charanck9]

…on idle

Add a timeout to the WAL read wait so that buffered entries are flushed even when no new data arrives. Previously, readPrompbFromWAL would block indefinitely on rNotify when the WAL was empty, preventing the truncation timer in continuallyPopWALThenExport from ever firing. This caused buffered requests to remain unsent until the next write.

Also add the exporter ID to WAL telemetry attributes for disambiguation when multiple exporters share a collector.

Description

Link to tracking issue

#49130
Fixes

Testing

Documentation

Authorship

• [yes ] I, a human, wrote this pull request description myself.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: charanck9 / name: charanck9 (b4ae555, cec7e22)

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[Copilot]

Pull request overview

This PR addresses an idle-stall scenario in the Prometheus Remote Write exporter WAL reader by ensuring the export/truncation loop can make progress even when no new WAL entries arrive, and improves WAL telemetry by adding exporter identity attributes to disambiguate metrics across multiple exporter instances.

Changes:

• Add an exporter attribute to WAL telemetry metrics for per-exporter disambiguation.
• Introduce a bounded wait (timeout) when the WAL read hits ErrNotFound, allowing the export loop to periodically re-check truncation/export conditions.
• On read timeout, opportunistically flush buffered requests when the truncation timer has fired.

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[charanck9]

updated

[charanck9]

resolved the comments

[github-actions]

This PR was marked stale due to lack of activity. It will be closed in 14 days.

[opentelemetry-pr-dashboard]

Pull request dashboard status

Merged · refreshed 2026-08-05 06:39 UTC

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[krajorama]

The fix is looking good, but please add chloggen entry and also split out the unrelated attribute change. Smaller PRs are faster to approve and merge.

[charanck9]

Comments addressed

[opentelemetry-pr-dashboard]

Hi @charanck9 — just a friendly reminder that this pull request is waiting on you.

There are still items that need your attention. See the dashboard status comment for the full list. You don't need to push a code change to hand it back — replying to move each discussion forward is enough, whether that's answering a question, explaining why no change is needed, or asking a follow-up. The dashboard then automatically routes it back to reviewers.

If you believe this pull request is incorrectly routed as waiting on the author, comment /dashboard route:reviewers to route it from waiting on the author to waiting on reviewers.

[singhvibhanshu]

/workflow-approve

[singhvibhanshu]

/rerun

[singhvibhanshu]

/workflow-approve

[otelbot]

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