The Global Hashrate: How bitcoind reacts to mining power

34. The Global Hashrate: How bitcoind reacts to mining power

The "Speed" of Bitcoin is always 10 minutes per block. But what if millions of new miners join the network? To keep the speed constant, Bitcoin has a "Difficulty Adjustment." Every 2016 blocks (about 2 weeks), every node in the world looks at how fast the last blocks were found. If they were too fast, the nodes make the "Puzzle" harder. If they were too slow, they make it easier. It is the "Thermostat of the Bit." It is the "Balance of the Billions." It is the "Equilibrium of the Energy."

The GetNextWorkRequired Logic

In src/pow.cpp, the node calculates the "Difficulty" of the next block. It is a mathematical formula that ensures Bitcoin stays on schedule, no matter how much electricity is thrown at it. It is the "Clock of the Consensus."

/**
 * Calculates the difficulty (Target) for the next block.
 * Ensures the network maintains a 10-minute block interval.
 */
unsigned int GetNextWorkRequired(const CBlockIndex* pindexLast)
{
    // Checking the "Time Taken" for the last 2016 blocks.
    // If it took less than 2 weeks, make the puzzle harder.
    return CalculateNextWorkRequired(pindexLast, nFirstBlockTime);
}

Explaining the Code: The Rhythm of Reality

1. nFirstBlockTime: The node compares the "Now" to the "Then" (2 weeks ago). This "Distance in Time" is the only thing that matters. Bitcoin doesn't care who the miners are; it only cares about the time. It is the "Truth of the Tempo." It is the "Purity of the Pace."

2. CalculateNextWorkRequired: The node adjusts the "Target" (the number of zeros required at the start of the hash). This is the "Volume Knob" of the Bitcoin network. It is the "Control of the Consensus." It is the "Mastery of the Moment."