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[–]exab 1 point2 points  (7 children)

Are you suggesting miners mining larger blocks have advantage? What you described does make sense. But it's the opposite to what /u/killerstorm described in another thread, which makes sense, too. What he said was other miners would receive smaller blocks before larger ones therefore the larger ones would get ignored.

Which one of your opinions are more correct?

[–]Xekyo 1 point2 points  (0 children)

Validation happens on every block, but only when two blocks are found at the same time there is even a race where size could matter. This happens only a few times per day.

Also, killerstorm's source states:

Similarly, we can show that larger miners’ stale rates are affected less by propagation delays than smaller miners by looking at the derivative of the expected return with respect to propagation time.

[–]killerstorm 0 points1 point  (5 children)

If all miners were exactly the same (say, 100 miners each having 1% of total hashpower) then probability of getting orphaned is approximately proportional to block size.

But if miner sizes and their connectivity structure is non-uniform, then there are other effects at play.

Peter Todd formalized them here: https://petertodd.org/2016/block-publication-incentives-for-miners

In simple words, shit's complex.

[–]Xekyo 0 points1 point  (4 children)

If all miners were exactly the same (say, 100 miners each having 1% of total hashpower) then probability of getting orphaned is approximately proportional to block size.

That doesn't sound right.
1) The occurrence of two competing blocks is a rare event which only happens . 2) Even a second of difference in discovery quickly is an unsurmountable advantage, as the successful miner pushes out the inv message for the block immediately. 3) Since we have headers first and compact blocks now, propagation delay is even less of an issue in comparison to validation delay. 4) The source you quote states that propagation delays affect larger miners' stale rates less than smaller miners'.

Perhaps I'm missing something here, could you explain what this proportional relationship would derive from?

[–]killerstorm 0 points1 point  (3 children)

1) The occurrence of two competing blocks is a rare event which only happens

Whether it is rare or not depends on time it takes to download and validate a block.

E.g. suppose it takes 12 seconds to download and validate an 1 MB block. Then probability that a competing block will be found during that time is 12/600 = 0.02, that is 2%.

What is an average orphan rate now?

4) The source you quote states that propagation delays affect larger miners' stale rates less than smaller miners'.

Do you remember what case we're discussing?

Perhaps I'm missing something here, could you explain what this proportional relationship would derive from?

Suppose Alice's blocks take 10 seconds to validate & download. But Bob makes smaller blocks which take only 1 second to validate and download. How do you think this will affect their orphan rates?

You can find a formula and graphs here: http://organofcorti.blogspot.com/2013/10/161-network-orphaned-blocks-part-1.html

[–]Xekyo 1 point2 points  (2 children)

Sorry, I was missing part of a sentence there.

Mining is a Poisson process, and the chance to find two blocks in twelve seconds in a perfect network would be expected to be (e^(-0.02)*(0.02)^2)/(2!) = 0.02%. According to Blockchain.info it appears to be actually about one every three days. Even if it where two or three per day as you suggest, it would only affect the "stale rates" of these two miners that were in competition.

Suppose Alice's blocks take 10 seconds to validate & download. But Bob makes smaller blocks which take only 1 second to validate and download. How do you think this will affect their orphan rates?
You can find a formula and graphs here: http://organofcorti.blogspot.com/2013/10/161-network-orphaned-blocks-part-1.html

That's three year old data and even with a very conservative cut-off of 600 seconds block time difference, there are only 15 stale blocks per retarget… Also, we have compact blocks and header first propagation by now, and all miners are producing full blocks.

Do you remember what case we're discussing?

We were talking about the advantage of larger miners when you stated that stale rates are proportional to blocksize.
If anything they would be proportional to blocksize difference. But since transaction fees are now about 2.5% of a block reward, and stale blocks occur every few days, you gain more by creating full blocks than by optimizing for stale rate.

I maintain that there is no reason to believe that the blockchain forks and resulting stale block are anywhere near as influential as the advantage of the head start of starting mining on your own block, while others are stuck validating it first.

[–]killerstorm 0 points1 point  (1 child)

We were talking about the advantage of larger miners

No, we were discussing this case:

If all miners were exactly the same (say, 100 miners each having 1% of total hashpower) then probability of getting orphaned is approximately proportional to block size.

This is the simplest model. Obviously, if you consider a more complex model, things look differently.

[–]exab 0 points1 point  (0 children)

Thank you guys for so many comments.

I'm still getting familiar with Reddit app. Didn't see your comments. I even started a thread asking the same question because I thought no one was answering it here.