Ethereum's Glamsterdam Upgrade Tests 200M Gas Block Limit

Ethereum (ETH) is conducting performance validation on its next upgrade, Glamsterdam, at a block gas limit of 200 million. This testnet setting does not confirm the mainnet limit yet. According to CoinDesk, the Glamsterdam testnet has continued confirming blocks under new block creation rules, with developers proposing the Sepolia fork as the next step for October 6, 2026.

The Ethereum execution client Nethermind completed all 2302 performance tests in 3 minutes and 15 seconds, processing 57.07 billion gas with an average throughput of approximately 29 billion gas per second. This is a benchmark result for the execution software, not the entire network's capacity. The testnet block gas limit increased from 60 million to 200 million, allowing more transactions like payments, token swaps, and smart contract executions per block. However, larger blocks may increase verification burdens and node operating costs.

The core technology of Glamsterdam is the Block Access List (BAL), which records accounts and storage data each block can access before execution to support parallel transaction processing and pre-loading. Ethereum Improvement Proposal EIP-7928 explains that BAL helps identify transaction dependencies for parallel disk reads and verification, though it remains under review.

Ethereum Foundation stated Glamsterdam focuses on creating an execution structure capable of handling higher gas limits through BAL and proposer-builder separation (ePBS). With ePBS, network data propagation time will increase from about 2 seconds to 9 seconds. The upcoming upgrade's main validation point is whether data propagation and verification can proceed stably while increasing block size.

Development tests include multiple execution and consensus clients such as Geth, Nethermind, Besu, Reth, Erigon for execution; Lighthouse, Lodestar, Teku, Nimbus, Prysm for consensus. Some client compatibility and performance validation are still ongoing. Devnet-11 specifications also include the 200 million gas setting, but results from controlled test environments cannot be directly extrapolated to mainnet performance.

The official roadmap lists the Sepolia fork date as October 6, 2026, with mainnet implementation expected in Q4 2026. Specific dates remain unconfirmed. Glamsterdam's schedule and scope may adjust based on Meta EIPs and test results. Developers will check client compatibility and performance after the October 2026 Sepolia fork before finalizing mainnet gas limits and upgrade scope.