Use ring buffer for pending Ether Deposits

[dantaik]

As of now, the EthDeposit[] ethDeposits is an ever growing array. It can be turned into a ring buffer for reducing gas cost. This will be a very good first issue for community developer to implement.

[Venoox]

I'd like to try this
Do you think it's a good idea to implement this with a fixed size array and having two variables to store the index of the start and the end of the buffer?

[cyberhorsey]

I'd like to try this Do you think it's a good idea to implement this with a fixed size array and having two variables to store the index of the start and the end of the buffer?

I think we can just modulo ID by the ringBufferSize? Haven't looked at the code much for this but I think that's how our other ring buffers are implemented.

[Venoox]

When the buffer is full and a new deposit is made, we overwrite the oldest deposit, is that correct?

I think we can just modulo ID by the ringBufferSize? Haven't looked at the code much for this but I think that's how our other ring buffers are implemented.

In this case I think it's different because we need to track the oldest deposit because when we process deposits we go from the oldest to the newest. So we need at least size and nextIndex variable to keep track of everything.

[dantaik]

@Venoox I assigned this feature to you. Do you think you can give us an ETA?

[Venoox]

A few days would be my best guess

[dantaik]

A few days would be my best guess

I got it done here: #13868

[Venoox]

Oh I've just finished working on it :/

[RogerRabbitTH]

Good