Constant eth_blockNumber invocation

[lazarmitic]

Hello, I noticed that as soon as I subscribe to an event using contract.on() with filter specified, ethers.js keeps calling eth_blockNumber (maybe every 2-3 seconds). I'm not sure why, and if this is an issue, but the problem I have with this is that my Alchemy usage is way over the top because of this. Is there any way I can disable this behavior?

[lazarmitic]

Just add to this, eth_chainId is also being called, but I switched to StaticJsonRpcProvider and it seems it has gone away, but eth_blockNumber is still being called a lot.

[ricmoo]

It’s every 4s by default, but it can be adjusted using provider.pollingInterval = 6000 for example (typed on my iPhone; there may be typos, but you should get the gist ;)) that to 6s.

That’s how events work. When you register an event listener, it needs to periodically poll the backend. The most efficient way to do this is to check if the block number has changed; since no other event can have happened in the meantime, and once it changes, all events are checked.

[lazarmitic]

Thanks. Is the situation any better if I use web sockets to connect to provider instead of http?