How much ADA stake do you need to be likely to make a block?

How much ADA stake do you need to be likely to make a block?

Here is my calculation for epoch 210 with stake pools making 10% of blocks and current total stake of 6.88b ADA.

1 slot/sec * 60 sec/min * 60 min/hr * 24 hr/day * 5 day/epoch = 432,000 slot/epoch
432,000 slot/epoch * .05 block/slot = 21,600 block/epoch
21,600 block/epoch * .1 spo block/block = 2,160 spo block/epoch
6,880,000,000 ADA / 2,160 spo block/epoch = 3,185,185 ADA/spo block/epoch

So in epoch 210, you need 3.2m ADA stake to be likely to make a block.
By the time decentralization reaches 100% and assuming 20b ADA total stake, you will only need 925k ADA.
I know it’s actually calculated based on the stake snapshot at the previous epoch boundary which is less than 6.88b.
Otherwise, let me know if there is something wrong with how I calculated this.

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That looks about right - obviously that amount will increase as total ADA delegated increases (d param being constant)

And keep in mind if you expand your epoch timeline, the amount of ADA required to mint a block becomes inversely proportional to the number of epochs considered - for example, a pool might mint one block every 2 epochs on average with a stake of ~1.6M ADA (total ADA staked being held constant of course)

EDIT - I seem to have missed your d param calc - I think out the gate d will be 0.975, so stake for a single SPO to mint a block starting out will be much higher

Is a slot not 20 seconds in Shelley?

No, a slot is one second, with a block coefficient of 0.5, so an average of 1 block every 20 seconds

Good analysis. How about the poolPledge amount?

I feel like you need enough staked + the right amount of poolPledge.

Yeah, this is going to make it harder for smaller pools.
New estimate for epoch 211 is 14m needed!
By epoch 214 with 10b stake we will be down to 4.6m needed.
By epoch 250 with 20b stake we will be down to 925k needed.

we’re still getting confirmation on initial d param

d = 0.975 out the gate would be a massacre to smaller pools

Charles confirmed he agree initial d should equal 0.9

That’s a relief!
With 7.6b stake that gets us to 3.5m ADA needed in epoch 211 and with 10b stake and delta-d of .025 that gives us 2.3m ADA needed in epoch 215.

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