I'd like to know the EVM gas limit of a single node with modern computing specs. My understanding is that the current gas limit of Ethereum(15m/block or 1m/s) is constrained such that all nodes in the network can verify blocks, hence why more centralised networks such as BSC can have a larger gas limit of ~80m/block or ~27m/s(given a ~3s block time) which is ~27x the Ethereum gas limit. So what would the EVM gas limit be if the network comprised of a single high-performance node?
My understanding is that there are multiple EVM implementations some more performant than others, e.g. Hyperledger Besu EVM > EthereumJ EVM.
Best Answer
There's no intrinsic limit; it depends on the hardware and the software implementation.
What limits the EVM is the design choice of the specific community that uses the EVM, because there is always a trade-off between decentralization and performance.
On one side, there's the full centralization. This lets you control all the data and operations and apply all the scaling mechanisms you want to increase the performance. Usually, you split the workloads in parallel to use multiple CPUs and DBs. The amount of gas/sec is only limited by your willingness to spend money on more hardware.
On the other side, there's the full decentralization. This is a game you play with all the other peers, so you need the lightest workload possible to achieve that, so literally, anyone can run it and stay in sync with all the other nodes. Not considering PoW for consensus but only computing power to validate blocks, Bitcoin is a masterpiece on this side: at maximum, your machine needs to elaborate ~1.5Mb of data every ~10 minutes.
In between, there are all the other choices between performance and decentralization. Ethereum poses that choice to a ~15 sec per block, with a max of 30M gas per block (15M gas target, dynamic up to 30M max). This limit is what now (mid-may 2022) the community considers a good balance between speed, decentralization, TPS, and security.
But I also remember when, years ago, the max gas per block was 3.1M, then 4.7M ;) And a lot of people were against more raises to 8M, 10M, etc. Even though a raise alleviates the need to have more space for more applications, you also leave behind more and more nodes that cannot sync without proper hardware - an NVMe SSD is currently mandatory if you want to stay in sync with the network - and you move the decentralization bar towards the centralization.
Note: Vitalik set this as a trilemma, not a dilemma, adding security as one of the elements to consider. For the sake of simplicity, I think this can be left out of the discussion.