Maximal Extractable Value (MEV) has emerged as a “dominant constraint on blockchain scaling,” according to a report by the Flashbots research group.
Experts have discovered that spam transactions generated by arbitrage bots consume block space faster than even high-performance networks can expand it.
“This is not a theoretical or isolated issue. We can observe it everywhere, from Solana, where MEV bots consume 40% of block volume, to the Ethereum L2 ecosystem,” they emphasized.
The researchers provided some data:
- in several leading rollups, spam bots accounted for more than 50% of gas consumption but less than 10% of fees;
- from November 2024 to February 2025, Base’s throughput increased by 11 million gas units per second — all of which was consumed by autonomous software.
According to the Flashbots team, projects are engrossed in the technical aspects of scaling networks but overlook the economic constraints imposed by market structure.
MEV bot operators exploit the low cost of transactions, sending vast numbers of them. In a cited example of a successful arbitrage deal, a bot earned $0.12 while paying $0.02 in fees.
However, the true cost of the operation is staggering, the experts noted. For one successful deal, a bot typically sends about 350 million transactions and consumes approximately 132 million gas — equivalent to nearly four full Ethereum blocks.
The economics of such activity ensure that one successful operation more than covers the costs of failures elsewhere. Essentially, bots function as search engines with built-in logic to execute a specific algorithm. They initiate a transaction to include it in a block and send numerous requests to decentralized exchanges in search of arbitrage opportunities, costing around 2.6 million gas. If no opportunities are found, the bot simply does nothing.
One catalyst for spam is the transition of networks to private mempools. This solution was intended to protect users from frontrunning. However, the primary method for MEV bots to profit in rollups is arbitrage. To access private information in pools, the software is forced to send transactions in every block, the experts noted.
In addition to low fees, they also cited the lack of an effective transaction auction mechanism — the order of inclusion in a block is roughly determined by gas consumption.
“The gap between fees paid and gas used shows that spam imposes enormous external costs on networks while providing disproportionately little value in return, which is indicative of a systematically inefficient market,” the researchers concluded.
The activity of bots leads to blockchain overload, increasing hardware requirements and raising fees for regular users, they added.
The solution to the problem, according to Flashbots experts, lies in implementing “programmable privacy.” This entails real-time user access to transactions with simultaneous software restrictions on the potential for information abuse.
Earlier, Ethereum co-founder Vitalik Buterin identified MEV as one of the main threats to network centralization, alongside liquid staking and the cost of running a full node.