BSC's Growing Pains: Optimization for Traffic Spikes

Today we're releasing the first optimization designed to handle the surge in traffic on BSC.

Problem

We observed that during high-traffic periods, many transactions weren't being included in blocks in a timely manner. This meant that even users who increased their gas fees (transaction fees) to expedite their transactions weren't necessarily getting the priority they expected.

Root Cause

While there are many potential contributing factors, a key issue was that validator nodes (the computers that process and validate transactions) weren't always prioritizing the blocks with the highest overall value (i.e., the most lucrative blocks based on transaction fees).

BNB Chain's current design prioritizes getting all transactions on-chain as quickly as possible, minimizing the average wait time in the transaction pool (mempool). This approach works well for most typical use cases. However, it's not optimal for the fast-paced, high-stakes world of meme coin trading, where small price fluctuations can significantly impact.

As shown in the diagram, when validators reach the block limit, they will cease accepting new bids from builders, even if the new bids contain higher block values. These higher block values are typically a result of increased gas prices, or smart contract transactions with higher gas costs, such as meme swaps.

Solution: Prioritizing Time-Sensitive Transactions & Enhancing Block Selection

We're refining our strategy to prioritize block value, especially when dealing with critical transactions. In other words, we will give transactions interacting with time-sensitive (meme coin) contracts a higher priority.

This upgrade will introduce a short waiting period before block sealing, as long as there is sufficient time within the 3-second block window(blocks on BSC are created every 3 seconds). This will allow validators to gather more bids, increasing the chance of incorporating the best ones and improving overall block building performance, especially during periods of high network activityThis change also provides more time for bid gathering, potentially leading to more efficient block building.

For details:

• https://github.com/bnb-chain/bsc/releases/tag/v1.4.18
• https://github.com/bnb-chain/bsc/releases/tag/v1.5.6