reverts wide fanout in broadcast when the root node is down (backport #26359) #27183
Conversation
This file contains 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
![mergify[bot]](https://avatars.githubusercontent.com/in/10562?s=60&v=4){kind=small}
A change included in #20480 was that when the root node in turbine broadcast tree is down, the leader will broadcast the shred to all nodes in the first layer. The intention was to mitigate the impact of dead nodes on shreds propagation, because if the root node is down, then the entire cluster will miss out the shred. On the other hand, if x% of stake is down, this will cause 200*x% + 1 packets/shreds ratio at the broadcast stage which might contribute to line-rate saturation and packet drop. To avoid this bandwidth saturation issue, this commit reverts that logic and always broadcasts shreds from the leader only to the root node. As before we rely on erasure codes to recover shreds lost due to staked nodes being offline. (cherry picked from commit 3b87aa9)
mergify
bot
added
the
automerge
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Outdated suggestions cannot be applied.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.
This is an automatic backport of pull request #26359 done by Mergify.
Mergify commands and options
More conditions and actions can be found in the documentation.
You can also trigger Mergify actions by commenting on this pull request:
@Mergifyio refreshwill re-evaluate the rules@Mergifyio rebasewill rebase this PR on its base branch@Mergifyio updatewill merge the base branch into this PR@Mergifyio backport <destination>will backport this PR on<destination>branchAdditionally, on Mergify dashboard you can:
Finally, you can contact us on https://mergify.com