[1500 TH] p2pool: Decentralized, DoS-resistant, Hop-Proof pool

[kano]

...
You see, even with this "bad luck", people are sticking to p2pool, as can be seen in the stats. Not because p2pool is necessarily paying out better than all other pools at any time, but because p2pool is superior and healthier for the whole bitcoin universe.
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Um - you wanna explain that one?
I'd like to see your opinion of how p2pool would cope with DeepBit's hash rate ...

[Syke]

I'd like to see your opinion of how p2pool would cope with DeepBit's hash rate ...

Average daily payout would be the same. Time to find shares would go up, and blocks found per day would also go up.

A slow 1 gh/s miner on p2pool gets a share on average every 45 minutes while p2pool finds a block every 4 hrs. Deepbit is 10 times the size of p2pool, so the 1 gh/s miner would get a share every 7.5 hrs and p2pool would find a block every 24 minutes. Large scale p2pool miners can adjust their share-rate, which will make shares easier for slow miners.

[rjk]

I'd like to see your opinion of how p2pool would cope with DeepBit's hash rate ...

Average daily payout would be the same. Time to find shares would go up, and blocks found per day would also go up.

A slow 1 gh/s miner on p2pool gets a share on average every 45 minutes while p2pool finds a block every 4 hrs. Deepbit is 10 times the size of p2pool, so the 1 gh/s miner would get a share every 7.5 hrs and p2pool would find a block every 24 minutes. Large scale p2pool miners can adjust their share-rate, which will make shares easier for slow miners.

Sure, if p2pool could scale infinitely. But there are a few things that would have to be resolved before we could get that kind of scalability.

[forrestv]

Sure, if p2pool could scale infinitely. But there are a few things that would have to be resolved before we could get that kind of scalability.

Huh? P2Pool would continue to work if one DeepBit-equivalent of miners joined. Variance would just go up. P2Pool adjusts the share difficulty to keep traffic/CPU usage constant.

[rjk]

Sure, if p2pool could scale infinitely. But there are a few things that would have to be resolved before we could get that kind of scalability.

Huh? P2Pool would continue to work if one DeepBit-equivalent of miners joined. Variance would just go up. P2Pool adjusts the share difficulty to keep traffic/CPU usage constant.

Right, I should clarify: yes p2pool itself should be able to handle it, but I doubt many miners would remain when the difficulty is so high that they may or may not get in a share in each block. It would have a negative feedback kind of effect, I would think.

[Syke]

Right, I should clarify: yes p2pool itself should be able to handle it, but I doubt many miners would remain when the difficulty is so high that they may or may not get in a share in each block. It would have a negative feedback kind of effect, I would think.

Who cares if you get a share in every block? You'll still get roughly the same number of payouts each day, even at a deepbit-size level.

Now if p2pool was 10 times the size of deepbit, then the difficulty would be so high that lots of small miners would not get daily payouts. That would be a problem. I look forward to p2pool growing so large that becomes a problem.

[ChanceCoats123]

But then you can have the larger (say 5ghash/sec +) miners use a > 300 share difficulty so the smaller miners can remain semi-profitable and use a lower difficulty. Since the larger miners have "lower" variance as-is, a slightly higher share difficulty will have little to no impact on their payouts, but greatly help the smaller guys.

[TheHarbinger]

Hopefully, auto-adjusting difficulty based on hashrate is something that will be coming in a future version.

[Ente]

Hopefully, auto-adjusting difficulty based on hashrate is something that will be coming in a future version.

That got me thinking.
Yes, this seems to be a good idea!
How to adjust the individual share difficulty?

- To have it similar to now (one share each 10 sec), each node would poll the number of nodes and the p2pool hashrate. If the individual hashrate is "high" compared to the average node's hashrate, make the local share-difficulty higher.
Quite complicated, maybe unstable, and all in all not too elegant, in my view..

- Drop the "one share every 10 sec" altogether. Make every node find one share, say, every 10 mins. Big miners will have a high local difficulty, small miners a low one. Depending on the amount of nodes, the sharechain would grow faster or slower than now. With those 10 mins per local share and approx 200 users at the moment, there would be a new share every 3 secs. This probably is too short, so we may make it "node, find a share every 30 mins!" for an approx sharechain-growth of one share every 10 secs.

This would not scale too far neither. But it would be a lot easier and with less drastic changes than the other, older proposals (sub-p2pool, multi-p2pool etc). So it might be a bridge-technology, as we say here.

Ente

[DeathAndTaxes]

The issue with those proposals is that without an enforced minimum difficulty cheating to reduce variance becomes trivial.  You create a tragedy of the commons situation where users unhappy with their share variance simply "cheat" and submit lower variance shares.  The network "speeds up" and avg LP interval falls from 10sec to 7sec or 5 sec.

If anything 10 sec is too short.  It is right at the inflection point.  Intervals shorter than 10s will result in significantly higher oprhan rates.  5s won't be double the 10s rate it will be more like 4x (so ~40% global stale rate). It is absolutely critical that the LP interval remain >=10s.

[DeathAndTaxes]

My estimated payout has gone down by about 50% for the past few days... Anyone have any ideas as to why this may be?
My hashrate has stayed about the same 371Mhash/s.

Take a look at avg block times for the last 5 blocks.

If we find 50% of the block (compared to expected) your payout will be 50% of expected.
If we find 200% of the blocks (compared to expected) your payout will be 200% of expected.

[DeathAndTaxes]

My estimated payout has gone down by about 50% for the past few days... Anyone have any ideas as to why this may be?
My hashrate has stayed about the same 371Mhash/s.

Take a look at avg block times for the last 5 blocks.

If we find 50% of the block (compared to expected) your payout will be 50% of expected.
If we find 200% of the blocks (compared to expected) your payout will be 200% of expected.

Ah, so just bad luck at the moment?
This is what I thought.

Yeah but a pretty brutally bad run of it.

[hashalfahalve]

Bam bam! 2 in a row, i'm rich!

[iopq]

Bam bam! 2 in a row, i'm rich!

we just got 4 blocks in a small amount of time

[gyverlb]

3 blocks in less than 30 minutes ? Is it Christmas already ?

[chunglam]

Bam bam! 2 in a row, i'm rich!

we just got 4 blocks in a small amount of time

5 blocks in 8 hours

[ChanceCoats123]

Just my fucking luck...  My dedicated miner runs for 10 days straight without issue, and on the day that p2pool finds a billion blocks, I come back to a rig that won't give video. Restart and everything is fine and dandy again. WTF is that?!?! It's like every 10-12 days this shit happens and on the day p2pool has good luck, my share count is 1/6 what it typically is. 

[kano]

Just my fucking luck...  My dedicated miner runs for 10 days straight without issue, and on the day that p2pool finds a billion blocks, I come back to a rig that won't give video. Restart and everything is fine and dandy again. WTF is that?!?! It's like every 10-12 days this shit happens and on the day p2pool has good luck, my share count is 1/6 what it typically is. 

You're not alone, I made the decision to use my computer to spend the day playing Borderlands and therefore not mining (so only .15BTC today)

The reason why pools exist in the first place - to reduce variance.
P2Pool just happens to reduce it way less than the other pools.

[Ente]

Just my fucking luck...  My dedicated miner runs for 10 days straight without issue, and on the day that p2pool finds a billion blocks, I come back to a rig that won't give video. Restart and everything is fine and dandy again. WTF is that?!?! It's like every 10-12 days this shit happens and on the day p2pool has good luck, my share count is 1/6 what it typically is. 

..let me know a few hours before your rig goes down, next time, ok? I would like a "warning, blockfinding-spree ahead!" warning system! ;-)

It all evens out after some time.

Ente

[kano]

Just my fucking luck...  My dedicated miner runs for 10 days straight without issue, and on the day that p2pool finds a billion blocks, I come back to a rig that won't give video. Restart and everything is fine and dandy again. WTF is that?!?! It's like every 10-12 days this shit happens and on the day p2pool has good luck, my share count is 1/6 what it typically is. 

..let me know a few hours before your rig goes down, next time, ok? I would like a "warning, blockfinding-spree ahead!" warning system! ;-)

It all evens out after some time.

Ente

Actually ... no it doesn't.
If you lose out in a good luck spree there is no guarantee whatsoever that you will get it back later.
There is no memory in bitcoin hashing.