Why the change in BlockByHeightArgs from U64 to U32?

Fuel Network
1

Hey all,

noticing a change in BlockByHeightArgs in fuel-core-client schema, from U64 in v0.20.4 to U32 in v0.21.0+

I can see the comment as:
“void possible truncation of higher bits. It may invalidate the code that truncated higher bits causing different behavior on 32-bit vs. 64-bit systems. The change affects some endpoints that now require lesser integers.”

and the PR:

Just curious why we expect only up to a 32 bit number here, surely we expect the node to accumulate over 2^32 blocks over time?

from:

#[derive(cynic::QueryVariables, Debug)]
pub struct BlockByHeightArgs {
    pub height: Option<U64>,
}

to:

#[derive(cynic::QueryVariables, Debug)]
pub struct BlockByHeightArgs {
    pub height: Option<U32>,
}

in this commit:

2

Hi there!
32 bits is generally sufficient to store block height for most blockchains.

2^32 ~= 4.3 billion. At one block per second, that would still be 136 years until an overflow would occur, and we can upgrade the network at that time if needed.

3

Ok cool, just checking it was an intentional change.

rough calcualtion:

beta-4 testnet height is currently 13138944 and since its announcement on the fuel blog is ~133 days. That’s about 3M blocks/ month. which means to get to ~4B blocks would take 119 years. I think were probably good :slight_smile:

((2^32)/(13138994/(133/30.41)))/12 = 119.138 years

in saying that, if mainnet is 5x the tx volume, its ~20 years. But i doubt there would be the same schema framework in that time.

1 Like