Glamsterdam Pushes Sepolia Toward Higher Capacity
Ethereum's upcoming Glamsterdam upgrade is being tested with a significantly larger processing budget on the Sepolia public testnet, giving developers a chance to evaluate how the network handles substantially more potential activity.
The upgrade activated on Sepolia Tuesday, allowing developers to test the changes in an environment where the tokens have no real-world value. By early Thursday, the network was producing blocks with a gas limit close to 200 million, compared with roughly 60 million before the upgrade.
Gas represents the amount of computational work required to execute transactions and other operations on Ethereum. When demand for block space increases, users can compete for limited capacity, which can contribute to higher transaction fees. A larger block allowance could therefore give Ethereum more room to handle activity before congestion becomes a major issue.
The Ethereum Glamsterdam roadmap outlines the broader upgrade work being developed for the network, including changes intended to improve Ethereum's capacity and efficiency.
Test Blocks Are Using Less Than Half the New Limit
Despite the much larger theoretical capacity, early Sepolia blocks have not come close to filling the new allowance.
A review of more than 25 consecutive test blocks found gas usage ranging from approximately 52 million to 92 million per block. That represents roughly 26% to 46% of the available capacity under the new limit.
The result suggests the testnet has significant unused headroom at this stage. However, the higher limit is designed to be tested under heavier workloads, because operating close to the maximum would place greater demands on the computers that maintain Ethereum's network.
The larger gas limit also does not mean Ethereum will automatically process three times as many transactions. Glamsterdam changes the gas costs associated with certain operations, meaning the amount of activity that can fit into a block depends on the computational requirements of those transactions.
Developers can follow the underlying client implementation work through Ethereum's execution-layer specifications and EIPs, where the technical changes behind Ethereum upgrades are documented.
Glamsterdam Changes How Ethereum Handles Work
The upgrade is also changing how Ethereum's computers organize transaction processing.
One key change introduces rules around the handoff between the participants responsible for assembling transactions and validators responsible for publishing blocks. The goal is to give validators more time to verify transaction calculations while maintaining the network's security requirements.
Another part of the design involves information about the accounts and stored data touched by transactions. Blocks can include lists identifying that accessed information, allowing software to retrieve relevant data in advance.
That could make it possible for unrelated transactions to be checked simultaneously instead of requiring every operation to be handled strictly one after another. In practical terms, the approach is intended to make better use of the computing resources available to Ethereum clients.
The Ethereum developer documentation provides background on how blocks, transactions, gas and Ethereum's execution environment work.
Higher Capacity Comes With New Testing Requirements
Increasing Ethereum's processing capacity also creates additional requirements for the computers running the network.
Glamsterdam adjusts the gas charges associated with creating and accessing stored data. Because applications can sometimes rely on specific gas assumptions, developers have been advised to retest software to ensure those assumptions remain valid after the changes.
This type of testing is important because increasing theoretical capacity is only useful if the network can maintain reliable performance while processing the additional workload.
The Sepolia test therefore gives Ethereum developers an opportunity to observe how clients behave under the new configuration before considering any deployment to the mainnet.
Sepolia Finality Remains Strong During Testing
The early test results have also shown strong participation from validators.
During a separate six-minute voting period early Thursday, all 32 scheduled blocks were proposed. At the same time, 99.97% of eligible testnet stake voted toward finality, the point at which Ethereum treats the transaction history as settled.
The result provides an early indication that the testnet is continuing to reach consensus while operating under the substantially higher gas allowance.
However, the Sepolia test remains only one stage in the upgrade process. Developers still need to assess performance, client behavior and application compatibility before Glamsterdam can move closer to Ethereum's mainnet.
Information about Ethereum's consensus and validator architecture is available through the Ethereum proof-of-stake documentation.
Hoodi Testnet Is Next on the Roadmap
The next public testnet in the Glamsterdam rollout is Hoodi, which is tentatively scheduled for October 27, subject to the results from Sepolia.
That date is not yet a final mainnet schedule. Ethereum developers have not announced an activation date for Glamsterdam on Ethereum's mainnet.
For now, the Sepolia rehearsal is focused on determining whether the network can safely operate with the substantially higher processing allowance and the other architectural changes included in Glamsterdam.
If testing continues successfully, the upgrade could eventually give Ethereum more room for transaction activity while changing how clients prepare, access and verify transaction data. The current Sepolia results show that the network has substantial unused capacity under the new limit, but further testing will be needed before conclusions can be drawn about real-world mainnet performance.
