fix(disk-buffer): Remove empty buffer on close #17247
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
Download PR build artifacts for linux_amd64.tar.gz, darwin_arm64.tar.gz, and windows_amd64.zip. 👍 This pull request doesn't change the Telegraf binary size 📦 Click here to get additional PR build artifactsArtifact URLs |
skartikey
approved these changes
Jun 27, 2025
mstrandboge
approved these changes
Jun 27, 2025
srebhan
added a commit
that referenced
this pull request
Jul 7, 2025
(cherry picked from commit 533e0a9)
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Summary
When fully emptying a disk-buffer and then restarting (i.e. shutdown and start) Telegraf then empty disk-buffer still contains a (masked) metric due to restrictions in the upstream library. At runtime this is not an issue because we keep track of the empty state of the buffer and do not send the metric again. However, when shutting down Telegraf the WAL file still contains the (masked) metric but the mask and the "empty buffer" flag gets lost as it is not persisted to disk. As a consequence, we will resend the last metric even though it already has been sent.
This PR deletes the WAL file(s) when closing the empty buffer to make sure we do not send the metric again. This code can likely go away again if either tidwall/wal#31 or tidwall/wal#29 are merged.
Checklist
Related issues
related to #16981