Christopher Haster
41 lines
1.0 KiB
Python
Executable File
41 lines
1.0 KiB
Python
Executable File
#!/usr/bin/env python
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import matplotlib
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matplotlib.use('SVG')
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import matplotlib.pyplot as plt
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import numpy as np
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matplotlib.rc('font', family='sans-serif', size=11)
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matplotlib.rc('axes', titlesize='medium', labelsize='medium')
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matplotlib.rc('xtick', labelsize='small')
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matplotlib.rc('ytick', labelsize='small')
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fig, ax = plt.subplots(figsize=(6, 3.5))
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ax.set_title('Metadata pair update cost')
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# multiplicative cost of metadata
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def cost(r, n, size):
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cost = n + n*(r*(size/n) / ((1-r)*(size/n) + 1))
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return cost / n
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t = np.arange(0.0, 1.0, 0.01)
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ax.plot(t, cost(t, 100, 4096))
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ax.set_xlabel('% full')
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ax.set_xlim(0, 1)
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ax.set_ylabel('multiplicative cost')
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ax.set_ylim(0, 12)
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xticks = np.arange(0.0, 1+0.1, 0.2)
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ax.set_xticks(xticks)
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ax.set_xticklabels(['%d%%' % (100*t) for t in xticks])
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yticks = np.arange(0, 12+1, 2)
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ax.set_yticks(yticks)
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ax.set_yticklabels(['%dx' % t for t in yticks])
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ax.spines['right'].set_visible(False)
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ax.spines['top'].set_visible(False)
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fig.tight_layout()
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plt.savefig('metadata-cost.svg', bbox_inches="tight")
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