Metrics.md

Metrics

Introduction

The server keeps a list of the last blocks in the mainchain. Using that list, it generates data that it sends to the client to be rendered.

The list of blocks (the blockchain) is kept by lib/history.js, a fragment:

var MAX_HISTORY = 2000;

var MAX_PEER_PROPAGATION = 40;
var MIN_PROPAGATION_RANGE = 0;
var MAX_PROPAGATION_RANGE = 10000;

var MAX_UNCLES = 1000;
var MAX_UNCLES_PER_BIN = 25;
var MAX_BINS = 40;

var History = function History(data)
{
	this._items = [];
	this._callback = null;
}

The callback function, if defined, is called when the data is changed, ie, a new block arrived to be processed.

Multiple Values

Block Time

A list of times to produce a new block, ordered by ascending height.

Difficulty

A list of block difficulty, ordered by ascending height.

Block Propagation

A list of times (delta 0.5 seconds), counting the number of blocks that propagate in that interval. Each block has many propagation times, one per reached node.

Last Blocks Miners

A list of miners ids, that mined the blocks in the current history.

Uncle Count

Count of uncles, in the current block history. Each count is the sum of uncle counts in 25 blocks.

Transactions

Number of transactions in the last blocks in current history.

Gas Spending

Gas amount spent in each executed block.

Gas Limit

Gas limit per block in history.

Single Values

Best Block

The number of the best mined block added to the main chain.

Uncles

Number of uncles in current block vs count of uncles in last 50 blocks.

Last Block

Time elapsed from last mined block.

Average Block Time

Sum of block times divided by number of blocks in history.

Average Network Hashrate

Difficulty of best block divided by average of block time (time since previous block)

Difficulty

Last block difficulty.

Active Nodes

Number of active nodes vs number of total nodes.

Gas Price

Gas price in node with best block.

Gas Limit

Gas limit in best block.

Page Latency

Latency obtaining data.

Uptime

Percentage of nodes uptime.