[DigitalToday reporter Chi-gyu Hwang] Ethereum's next major upgrade, Glamsterdam, has passed its first test. Glamsterdam was applied to the Sepolia testnet on Oct. 6 (local time) and proceeded to block finalisation without major issues.

Glamsterdam is a name combining the consensus-layer upgrade Gloas and the execution-layer upgrade Amsterdam.

According to Bankless, Ethereum researchers are encouraged by progress so far. Barnabe Monnot (바르나베 모노), a researcher at EthLabs, said on social media platform X (Twitter) that once the upgrade is complete, the size of Ethereum's main chain (layer 1) will increase by at least three times and smart contract size by 2.5 times. Toni Wahrstaetter (토니 바르슈테터), a researcher at the Ethereum Foundation, called it the biggest throughput expansion since Ethereum's launch.

In numeric terms, the changes Glamsterdam could bring are seen as even more tangible.

Ethereum blocks have an upper limit on throughput. This is called the gas limit. Glamsterdam is designed so the network can handle raising this limit from 60 million to about 200 million. That would be an increase of about 3.3 times.

Ethereum mainnet gas limits stayed around 30 million for several years before rising to 60 million in three steps in 2025. Even when the London upgrade in 2021 doubled the maximum block size, the target was 15 million.

Even if the upgrade is applied, throughput does not immediately jump threefold. Bankless reported that Glamsterdam changes how blocks are made so it is safe to enlarge them, and validators decide later how much to raise the limit in practice.

Glamsterdam includes 18 Ethereum Improvement Proposals (EIPs). According to Bankless, there are three key points.

The first is EIP-7732, which centres on applying ePBS (enshrined Proposer-Builder Separation).

Under the current structure, specialised builders create blocks and pass them to validators via intermediaries called relays. With ePBS, a proposer first commits to a bid signed by a builder, and the builder later reveals the full block. This increases the time most validators have to verify transactions to about 4 to 9 seconds. With more than twice as much time to check, the network can handle including more transactions in a block.

The second is EIP-7928, a block-level access list (BAL).

It is a method of attaching in advance a list showing which data a block will access and how values change after processing.

At present, transactions must be opened to see which data they access, so they are processed one by one in sequence. With a list, needed data can be fetched in advance and multiple transactions can be checked at the same time. Using a factory analogy, ePBS extends inspection time, while BAL can be seen as enabling multiple assembly lines to run at once.

The third is an expansion of contract size and fee adjustments. Under the upgrade, the maximum size of Ethereum smart contracts increases from 24KiB to 64KiB. Large services have had to split programs into multiple pieces because their code exceeded the limit, and the upgrade is expected to reduce that burden.

The remaining variable is the schedule. The next step after the Glamsterdam upgrade is to be deployed on the Hoodi testnet. Oct. 27 is being mentioned as a tentative date, but nothing has been confirmed. The target for mainnet deployment is the fourth quarter of 2026.

Glamsterdam had originally been set for the first half of 2026, and its Sepolia deployment was pushed back to Oct. 6 from Aug. 3. As a result, the next schedule could also change again.

The Ethereum Foundation warned that problems could occur if wallets, indexers and gas estimation tools that assume a fixed upper bound for the gas limit do not update for the Glamsterdam upgrade. Bankless reported that activities that create many new accounts and storage, such as airdrops, minting and creating new wallets, could also increase cost burdens.