Trying to send transaction on next block

Question

I'm trying to understand block time and speed of transaction. For now I'm testing on Binance Smart Chain and then I will go to ethereum network.

I have a simple code in nodejs using web3 library, I'm connected to a node via websocket :

• I subscribe to 'newBlockHeaders' events
• Once I get a new block I use web3.eth.accounts.signTransaction and web3.eth.sendSignedTransaction to send a test transaction

My transaction is ALWAYS 2 blocks after the received block event. I want it to be 1 block after.

Looks like confirmation time is about 6 sec so 2 blocks makes sense. But how to place my transaction on just 1 block after the event received?

Answer 1

When a client receives a block it is likely the next block is already being mined. Using a very high gas price may encourage miners to include it in the next block but even in that case it is not a sure thing. Also a chain reorg may affect the order later.