Ethereum Delays Glamsterdam Activation on Hoodi, Removes Oct. 26 Date
Key Facts
The Ethereum Foundation announced on October 22 that it was postponing the Glamsterdam upgrade on the Hoodi testnet, where activation had been scheduled for October 26 at 17:42:48 UTC. The foundation said protocol developers made the decision at ACDE meeting No. 248 to allow further investigation of how proposal EIP-8037 interacts with smart contracts on mainnet. No new Hoodi activation date was set. The change removes the activation date from the updated configuration; it does not cancel the upgrade permanently. The foundation also confirmed that its announcement concerns the Hoodi network and does not set a date for Glamsterdam activation on mainnet.
Under the revised configuration, Amsterdam activation on the execution layer and Gloas activation on the consensus layer were removed from the Hoodi schedule. The schedule to raise the testnet’s gas limit to 200 million at the previously planned activation epoch was also removed. The foundation said the update rolls back a future upgrade configuration and does not reset Hoodi’s chain history. As a result, October 26 is no longer listed, and the new configuration contains no alternative epoch or time. The change also affects the gas limit increase plan that had been tied to the same activation.
The delay is linked to a review of how changes to gas accounting affect the behavior of existing contracts. The Ethereum Foundation explains that EIP-8037 increases the cost of state creation and measures it separately, while EIP-8038 updates state access costs. The changes aim to align gas prices with the resources used by the network. According to ChainSecurity’s analysis, state gas accounting and operation repricing can change the amount of gas required for a call, as well as the gas left to a contract after a failed call. A difference in these amounts could cause a failure-handling path to complete work that previously reverted.
ChainSecurity says some contracts record a failed call or switch to a fallback path afterward, making the amount of remaining gas consequential. A malicious caller could provide a valid operation with less gas than it needs to succeed, while leaving enough for the contract to record the failure. In this scenario, an attempt that could have been retried may become a permanent failure. The analysis gives the example of creating a new storage slot: state creation costs 97,920 state gas under the calculation shown, with separate execution fees added. The example shows how the cost accounting structure changes; it does not mean that a deployed contract has already been harmed.
The foundation had said that replaying historical mainnet transactions under the new gas schedule revealed a small group of contracts that rely on assumptions that could change, potentially causing them to fail or perform worse unless updated in advance. It added that the status of most contracts that showed problems could be addressed by increasing the gas limit, and that the vast majority of contracts are unaffected. The last review of state operation prices, according to the foundation, was in the 2021 Berlin upgrade. Since then, Ethereum’s state has grown, with growth accelerating as gas limits increased. This context places the compatibility review within a broader discussion about updating prices to reflect the network’s resource use.
Glamsterdam combines the Amsterdam upgrade to the execution layer with the Gloas upgrade to the consensus layer, and its main changes include separating block building from proposing and block-level access lists. Sepolia activated the upgrade on October 6, before the date previously scheduled for Hoodi. For mainnet, the roadmap had shown the fourth quarter of 2026 as the expected period, while noting that the date was unconfirmed. After the delay, the foundation announced no replacement date for Hoodi or date for mainnet. Coverage of the developers’ meeting indicated that a December launch had become unlikely, while the official timing remained unconfirmed.
The foundation asked Hoodi node operators and validators to review the execution- and consensus-layer client instructions before October 26 and make sure the old activation had been removed from their configurations. It listed revised releases for some clients, including Lighthouse v8.3.2, Lodestar v1.50.1, Prysm v7.3.1 and Teku 26.10.2 for the consensus layer, and Besu 26.10.1, Ethrex v30.0.1-rc.2 and Nethermind 2.2.1 for the execution layer. It urged operators to update both layers to releases whose notes confirm removal of the October 26 activation. The foundation said mainnet users and ETH holders do not need to take action as a result of this update. The timing of upcoming phases remains subject to completion of the review of the proposal’s interactions with contracts.