On Wednesday, the Beacon Chain – the core of the Ethereum 2.0 ecosystem – experienced a blockchain reorganization 7 blocks deep. That means that 7 blocks worth of its most recent transactions were effectively reversed on Wednesday.
The Meaning of Blockchain Reorgs
A blockchain reorganization occurs when nodes cannot agree on the canonical order of blocks. This can be caused by a number of factors, which differ between proof of work and proof of stake systems.
Ethereum co-founder Vitalik Buterin claimed last year that Ethereum’s switch to POS would significantly reduce the probability of blockchain reorgs.
However, as Gnosis co-founder Martin Köppelmann explains, yesterday’s reorg proves that this was an overly-optimistic assumption. “We have not seen 7 block reorgs on Ethereum main net in years,” he said.
Köppelmann believes that a 7-block reorg – despite only representing 84 second worth of transactions – is still a massive issue. If it had taken place after the merge, it may have interfered with a host of Ethereum applications. Problems could have included a replaying of all DEX trades, oracle updates, liquidations, and more.
Thankfully, the cause of the reorg was not a fundamental flaw in Ethereum’s proof of stake, and will likely not be repeated. Apparently, a new upgrade called “proposer boost fork” was rolled out improperly, which changed the behavior surrounding what clients determined as the “best block”. Different chain implementations rolled out the update at different times, causing delay between when each client agreed on the canonical chain.
Köppelmann believes that such updates should be approached more mindfully in the future. If this occurs, future block reorganizations of this size are unlikely.
When is the Merge?
The Merge – the nickname for Ethereum’s upcoming upgrade to proof of stake – has been delayed multiple times over many years. Buterin promised last year that it should take place before July of 2022, but this now looks unlikely. Days ago, he even suggested that new predictions for an August upgrade may suffer further, months-long delays.
After the Merge, the creator believes Ethereum will be more than halfway complete. However, another four major stages of network improvements will be required to see it scale, and grow more decentralized.
The Merge is intended to provide a foundation for bettering Ethereum’s scalability and lowering its carbon footprint. Over 10 million Ether are already being staked on the beacon chain in anticipation of the upgrade.