Limit CPU usage by a quota

[rraallvv]

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Question or Feature Request

When deploying multiple miners to systems with different specs, I always find myself having to tweak throttleAfter and throttleWait for each miner separately. Since the CPU usage is highly dependent on those values, and they don't have the same effect on each separate worker. That's I was wondering whether it would be possible to use something like follows in the function _singleMiner in MinerWorkerPool.js to be able to limit the CPU usage to a quota instead of using throttleAfter and throttleWait

_singleMiner(nonceRange) {
    const start = Date.now();

    while(...) {
        ...
    }

    const end = Date.now();

    if (this._miningEnabled) {
        setTimeout(() => this._singleMiner(nonceRange), (end - start) * fraction);
    }
}

The variable fraction could be calculated from a desired CPU quota like this:

miningTime = end - start
idleTime = fraction * miningTime

doing some math:

CPUquota = miningTime / (miningTime + idleTime) * 100
         = miningTime / (miningTime + fraction * miningTime) * 100
         = 1 / (1 + fraction) * 100

Which give us:

fraction = (100 / CPUquota - 1)

Where CPUquota could be just some value passed to the miner, just like throttleAfter or throttleWait