Keep transactions from only one chunk in ChunkStateWitness

[jancionear]

Currently ChunkStateWitness contains transactions from two chunks:

• transactions - transactions added in the previous chunk
• new_transactions - transactions added in the current chunk

To limit the state witness size we have a size limit for the sum of those two fields (combined_transactions_size_limit), but the fact that the witness contains transactions from two chunks really limits the throughput of incoming transactions.

For NEAR DA we would like to be able to ingest 4MB on every chunk, but this would require combined_transactions_size_limit to be 8MB, as we'd have to include 4MB of transactions from the previous chunk and 4MB of transactions from the current one.

It would be nice to only have transactions from one chunk inside the witness, it'd double the throughput.

Refs: zulip discussion

/cc @pugachAG @staffik

[staffik]

@jancionear How criticial do you think it is for mainnet launch? I wonder whether to prioritize this over current issues investigation.

[jancionear]

@jancionear How criticial do you think it is for mainnet launch? I wonder whether to prioritize this over current issues investigation.

I think it can be done after the mainnet launch, it's a nice optimization but it isn't that critical. AFAIK it would really help NEAR DA, as it doubles the network throughput.