Four health indicators of the Ethereum 2.0 network

特邀专栏作者

2020-02-21 10:12 (UTC+8)

This article is about 2763 words, reading the full article takes about 4 minutes

In this article, we'll define some of these metrics, explain what they mean, how they're measured, and how they can be used to discern the health of your network.

AI Summary

Expand

In this article, we'll define some of these metrics, explain what they mean, how they're measured, and how they can be used to discern the health of your network.

Editor's Note: This article is from:Ethereum enthusiasts (ID: ethfans)Editor's Note: This article is from:

Ethereum enthusiasts (ID: ethfans)

, translation & proofreading: Min Min & A Jian, reproduced by Odaily with authorization.

There are many articles on how to measure the performance of Ethereum 2.0 validators, but very few articles on how to evaluate the health of the entire Ethereum network. Here are a few important indicators that provide useful information for network operators and those who want to participate in the Ethereum network (whether operating a node or directly becoming a validator). In this article, we'll define some of these metrics, explain what they mean, how they're measured, and how they can be used to discern the health of your network.

network activity

Network liveness is a measure of how quickly new blocks on the Ethereum 2.0 blockchain can be finalized. The importance of this indicator is that before a block is finalized, it may be replaced, so the transfer in the block cannot be accounted for. If the Ethereum 2.0 blockchain cannot consistently endow blocks with finality, it cannot achieve its fundamental goal of providing immutability of transactions and state.

Network activity is scored on a scale from 0% to 100%. A score of 100% means that blocks are finalized as quickly as the protocol allows; a score of 0% means that blocks are not finalized very often. If network liveness is 0%, validators will start losing money no matter how well they behave, because the network as a whole cannot finalize blocks.

Network liveness is usually 100%, dropping to 50% during periods of poor network communication between validators. If the network liveness value drops below 50%, there is a serious problem with the network.

image description

-Figure 1: Network Activity Value Range-

How to calculate network activity value?

The current epoch can be calculated using the current timestamp and some network constants:

Finalization slots are obtained from active Ethereum 2.0 nodes.

Participation Rate

What is an engagement rate? Where is it important?

A good participation rate is between 80% and 95%. If the participation rate drops below 67%, blocks cannot be finalized and network activity begins to decline.

image description

-Figure 2: Participation rate range-

secondary title

How to calculate participation rate?

It is worth mentioning that there are many different filling methods for the value of the numerator. It could be the number of attestations contained in blocks in the last epoch, it could be the number of attestations in the last epoch seen by the node, it could be the number of attestations contained in blocks from the last epoch, etc. It is also possible to obtain a lagged participation rate using lagged data, for example using the relative quantity for the penultimate period. The exact method used to calculate the engagement rate depends on the user and the data available to them.

Attesting validators are those that are considered active, exiting, or slashed based on the validator lifetime.

secondary title

What is the expected validator reward? Where is it important?

Most validators participate to earn rewards. Expected validator income refers to the expected income that a validator can get from performing his duties for one year, which is measured by the ratio of the expected available ETH divided by the amount of pledged ETH.

-Figure 3: The maximum reward value of the verifier vs. the total number of verifiers submitting proofs (valuation)-

Whether the reward level can be regarded as generous depends mainly on the cost of the validators participating in the witness. The costs here are varied, and the costs must be understood before the rewards can be considered. It is worth noting that the cost of running a validator node is usually calculated in fiat currency, while the reward is calculated in ether currency, so an exchange rate needs to be used. Assuming that the monthly cost of each validator is $25, and the price of ETH is $200, the income level is as follows:

image description

-Figure 4: Expected benefits after deducting costs-

secondary title

How to calculate expected validator rewards?

The expected verifier income can be calculated according to the specific number of verifiers according to the above figure; the number of verifiers who provide witness messages can be obtained from the Ethereum 2.0 node.

Pledge validity

Staking Effectiveness is a measure of the percentage of ETH staked by a validator. Ethereum 2.0 uses an indicator called the effective balance to judge the weight of the proof, and the weight of most verifiers will be discounted, that is, the actual balance is higher than the effective balance. For example, if a validator has a balance of 31.7 ETH and an effective balance of 31 ETH, 0.7 ETH of this is wasted during the validator's process of generating attestations. As the validator's actual balance changes, so does the amount of "waste" ETH, but it is rarely equal to zero.

The importance of stake availability is that the more ETH there is to secure the network, the better. As far as network security is concerned, ETH that is locked by validators but cannot be used to generate proofs is a waste. In addition, it is also important for each staker, because the reward is calculated based on the effective balance, and a lower stake validity will reduce their expected reward from the operation of the validator.