On May 11th and 12th, the Ethereum network was hit by two separate incidents that caused a significant loss in Finality. According to a recent tweet by Glassnode, over 60% of validators on the network stopped performing their duties during these incidents.
Finality is a crucial state where a supermajority of validators (2/3 of the total stake) have attested to the final state of the blockchain, ensuring that a block and its processed transactions cannot be altered or removed from the blockchain.
Due to the absence of up to 60% of validators, the Ethereum chain’s performance was impacted, leading to a degradation in performance.
Daily slots of about 3.68% were missed, and 253 blocks were not proposed on time. However, this was still lower than the 658 blocks missed during the Shapella upgrade.
On a more technical level, some consensus layer clients encountered older attestations and were forced to load up older states for verification, which caused these systems to overheat and malfunction.
Nevertheless, some clients did not encounter this issue due to a difference in design approach. Hence, validators running these clients continued to process transactions and produce blocks.
In both incidents, the affected validators returned online within 20 minutes and an hour, respectively, with the participation rate quickly jumping back to over 98%.
Inactivity Leak: A First For Ethereum Network
Fortunately, these incidents did not affect end-users on the Ethereum mainnet, and transactions continued to be processed as usual. However, the second incident resulted in the first-ever Inactivity Leak, an emergency state utilized to recover Finality on the Beacon Chain.
An inactivity Leak is a state where inactive validators are increasingly penalized until they are diluted out of the chain or begin participating once more.
During the Inactivity Leak, the amounts subtracted from validators’ beacon chain accounts are effectively burned, resulting in less ETH issuance during that time.
Nevertheless, these incidents serve as a reminder of the importance of network security and the need for a reliable and robust validator ecosystem. However, the Ethereum community must continue to take proactive measures to prevent future incidents and ensure the smooth operation of the network.