Updating proposer calculator on restart #1915
Merged
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
igorcrevar
approved these changes
Sep 19, 2023
Stefan-Ethernal
approved these changes
Sep 19, 2023
Stefan-Ethernal
force-pushed
the
EVM-828-sol-eng-midnight-society-restarting-the-chain-after-blocktime-change
branch
from
6d81c2b
to
628182e
Compare
Stefan-Ethernal
deleted the
EVM-828-sol-eng-midnight-society-restarting-the-chain-after-blocktime-change
branch
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
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Outdated suggestions cannot be applied.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.
Description
This PR fixes the inconsistent state of the proposer calculator on node restart. The inconsistent state occurs when the proposer calculator's height is less than or equal to the current block number. It can occur when the node is stopped at a moment when a block is inserted into the blockchain, but the post-block function for the proposer calculator doesn't update the snapshot database. Later, when the node is started again, if the majority of valid nodes have a consistent state, everything will be okay, as the bad node will receive the new block from the syncer, which will fix the problem. However, if the majority of validators have an inconsistent state, consensus for the new block cannot be reached, and new blocks won't be produced. The solution for this is to align the proposer calculator on node startup by updating the proposer calculator's height based on the height of the current block (the last inserted block).
Changes include
Checklist
Testing
Manual tests
I've tested this scenario by changing the code by adding additional time. Sleep in order to be able to reproduce the bug and thus confirm that the scenario is for sure the one described above. This code that reproduces problematic scenario each time cannot be used as an official test and it was only used to confirm the problem and verify the fix. Also the test for a bulk drop is adapted and it probably can cause this scenario on rare occasions.