Estimate Costs for Burst Mode

math.py

#!/usr/bin/env python3

# TODO -- Debug this logic. It doesn't quite seem to give the expected results.

import csv

filename = 'pre-failover.csv'
HOUR = 60
max_wait = 1
TASKS_PER_INSTANCE = 6
INSTANCES = 4
OUTPUTS_PER_FILE = 5
AVERAGE_GB_PER_FILE = 0.138
USD_PER_GB = 1.35

MAX_SLOTS = TASKS_PER_INSTANCE * INSTANCES


def parseRow(row):
    (processingStr, waitingStr) = row
    processing = float(processingStr.replace('%', ''))
    waiting = float(waitingStr.replace('%', ''))
    return processing + waiting


if __name__ == "__main__":
    with open(filename, newline='') as csvfile:
        data = csv.reader(csvfile)
        next(data)  # Skip header row

        # Initialize state
        prevQueue = 0
        totalQueue = 0

        waitingMinutes = 0
        totalMinutes = 0

        totalCost = 0
        totalGb = 0

        print('\n-------------------------------------------------')
        print('Simulating %d minute max wait time' % (max_wait))
        print('-------------------------------------------------')

        for row in data:
            totalMinutes += 1

            newQueue = parseRow(row)
            deltaQueue = newQueue - prevQueue
            totalQueue += deltaQueue

            if totalQueue > 100:
                waitingMinutes += 1
            else:
                waitingMinutes = 0

            # Simulate burst mode turning on
            if waitingMinutes > max_wait:

                # Calculate the cost of the burst firing
                # TODO - analyze this logic carefully. I suspect there's a logic error here...
                waitingQueue = totalQueue - 100  # Exclude our reserved instance capacity
                burstFiles = (MAX_SLOTS / OUTPUTS_PER_FILE) * (waitingQueue / 100)
                burstGb = burstFiles * AVERAGE_GB_PER_FILE  # Lower bound estimate: skip cost per output (which is 20% of source right now)
                burstCost = burstGb * USD_PER_GB
                print('BURST %d GB / $ %.2f' % (burstGb, burstCost))

                # Update the running totals
                totalGb += burstGb
                totalCost += burstCost

                # Reset state
                totalQueue = 100
                waitingMinutes = 0

        # Summarize totals
        if totalCost > 0:
            print('-------------------------------------------------')

        print('TOTAL %d GB / $ %.2f\n' % (totalGb, totalCost))

        print(' - %d hours simulated, (%d%% of a 750 hr month)' % (
            totalMinutes / HOUR,
            totalMinutes / (750 * HOUR) * 100
        ))

        print(' - %d%% of a 10 TB used during %d minutes' % (
            totalGb / 10000 * 100,
            totalMinutes
        ))

        if totalGb > 0:
            print(' - %.1f projected days of usage from 10 TB credit ' % (
                (10000 * totalMinutes / (24 * HOUR)) / totalGb
            ))

        print('-------------------------------------------------\n')

pre-failover.csv