Breakout session: cost model

Questions addressed

When is the measure of the namespace set? and how?
- How do regions work? How do regions impact costing?
How do you split out rewards for validators?
How is rent distributed?
How do contracts move across regions?
What happens when a contract runs out of Phlo?
Does Phlo persist from block to block during computation?
If 2 '@foo' contracts are deployed simultaneously, how is it determined which contract points to which wallet

If east costs more than central, and
- If there are more validators in a region, then it would cost more to operate in that region
- IS there a concept of the number (min and max) of the validators in a region?

PROPOSAL: Distribute rewards evenly (or even stake-weighted) to validators
- Problem: Free-riding:
CONCERN: What if a validator turns on and off every 45 seconds, and then they get rewards (free-riding)
- Free rider is a validator who watches the results of other validators and says they did it to get the reward
- This problem is not unique to RChain. It is a problem that needs to be solved.
- IDEA - TSA solution: To solve for an inattention problem, TSA inserts knives into bags that are not there.
  - Insert a bogus transaction to force the network to ID, those who validate are free-riders
- IDEA - The abusive boyfriend protocol
  - You know there are lies out there, if you sign something without checking it, then you are a free-rider
  - This is part of the consensus protocol
- IDEA - Rewards are only distributed after the block is finalized. If you're block is not doing anything, then no rewards for you "Little Red Hen" concept

Ways to make REV

How and when do fees change?

ANSWER: It is determined by the region (the sum of measure of the regions) determined by the genesis block.
- Regions establish the cost measures
Why can't it be the namespace?
- Example: namespaces could come up with a costs model (A v B), but then C wants to join
- ANSWER: This is prohibitive because it would require storage at the top
It is important that the measures of the regions don't change frequently because it will impact trust
You want namespaces that are in a federated, competitive market
- You may decide to trade slowness for safety
- You may decide to trade fastness for insecurity
- What we want from the network is to have both extremes in the network

Costs increase as safety goes up
- Ideal is to find a place in the middle where the least achievable amount of safety is allowed.

What's the difference between a region and a namespace?

Should validators decide costs by region?

How do you move a contract from region 1 to region 2?
What if a region becomes a cartel?
- Can validators in a region alter the price?
- There is a dis-incentive because no one will want to join
- But the ones stuck there will be held hostage
The solution is that to become a validator you have to be approved at the top level.
- Local price information is published globally
- You need agreement globally to change the price regionally
Are costs determined by humans?
- Humans establish the region and standards and push for global consensus
- Then the market can choose to participate in the region or not
If a region can identify a region that is a cartel, you can set a standard not to process those transactions. You can set the stand
- How much would Target spend to underprice Walmart?
- You want everyone to lower the price as much as possible to encourage transaction volume (like multiple fast food locations at a single intersection)

ANSWER - When you deploy something there is a wallet in the same message, so you just pass the wallet

The block records what has happened so far and add a notice that it's out of phlo
The network would store a record (a try) of contracts that ran out of phlo
- Hash the computation and store the effect as a record in a log of contracts that ran out of phlo
- Need to avoid replay attacks, where more than one person adds phlo to refuel the contract

As time goes on the number of effects you have to keep track of more and more
You do have to keep track of what has been revived - this is the tricker part, trickier than reviving
- What data structure would you use to track?
- A complete try leaves a hole, which results in rewriting the try

Runs until there is nothing left to run
Allows you to track when you're done
It doesn't have to be sequential
Kyle advocates to not run code that creates multiple races
- The network will decide who wins what race
  - Could create slowness on the network
    - If you don't want to slowness due to resourcing for race designs, then don't write code like that. Suggestion is to write it differently.
    - Is it expensive and slow for the person writing it or for the validators?
If running to quiescence then, one validator decides the race
- Race winners are fair. They are just non-deterministic
- If you want fair, write better code
Example: Network has 100 validators, you opt for validation from three.
- Transaction sent to 3 with a bunch of serial races, each validator calculates a trace and broadcasts to the network, the network decides the winner
- No single actor knows which one will be selected as the winner (it's safe and not fair)
You deploy and pay for all computation until it reaches quiescence
- This disincentives others for writing on the platform (ex data feed will be expensive)
- Nash, don't do this because no one will write an oracle if this is the case (required to run to quiescence)
- Joe proposes deployer pays. If you invoke someone else's contract, you pay for it.
This is Kyle's recommendation

Deploy (P) and Deploy (Q) exist and don't overlap overlap in the tuplespace.
- Henry needs to know this as it relates to storage
- We want to be able to persist code is such a way that when someone runs it you continue paying
What happens when the cost of running a contract fluctuates?
- The phlo-balance-pointer solves for this
Deployer pays until quiescence
- Mike wants I want to send data and not pay for it
- Think about each term of a contract being it's own tiny contract
Would people have phlo wallets?
- No. You don't get phlo back if it runs to quiescence
- If there is any phlo let at the end of all your reductions, then you get change
  - Incentivizes running the contract to completion
  - Storage layer keeps a reference counter. If phlo not zero, then give change.
If your code produces things in another namespace, your reference count remains 1 until you hear back from the other namespace that they've reached quiescense
- Your phlo number would have to be synced across namespaces if contract is run across namespaces

Example, chess clock. Timed when contract is in the tuplespace, timed when contract is being executed. Rent is being charged when you're not running