The Ethereum beacon chain recently experienced two periods where finalization was delayed and an inactivity leak began. Although it was still possible to transact on Ethereum during these periods, the blocks were not yet immutable, and could, under certain circumstances, end up reverted.
One occurrence took place for about an hour on May 12, and another period lasting less than half an hour happened on May 11. Beaconcha.in shows significant reductions in attestations for epochs 200,552 to 200,554 and 200,750 to 200,758.
The exact causes of these incidents remain unclear. However, both the Prysm and Teku consensus clients have released updates, suggesting that the issues might be linked to unexpectedly high resource consumption.
- When less than two-thirds of validators are online, Ethereum initiates an ‘inactivity leak,’ whereby offline validators gradually lose their staked ether.
- This process continues until the offline validators have been reduced to a small enough proportion, prompting finalization to resume.
- It’s worth noting that this was the first time the inactivity leak occurred on the Ethereum mainnet.
Ben Edgington, the founder of the Teku client, estimated the total inactivity leak at 28 ether during the longer inactive period.
Since epoch 200,758, the network has appeared stable. We await further details to learn why so many validators simultaneously went offline.