40 lines
990 B
Python
40 lines
990 B
Python
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#!/usr/bin/env python3
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size_classes = [
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16, 32, 48, 64, 80, 96, 112, 128,
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160, 192, 224, 256,
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320, 384, 448, 512,
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640, 768, 896, 1024,
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1280, 1536, 1792, 2048,
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2560, 3072, 3584, 4096,
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5120, 6144, 7168, 8192,
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10240, 12288, 14336, 16384
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]
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def page_align(size):
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return (size + 4095) & ~4095
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max_bits = 256
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max_page_span = 16
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print("maximum bitmap size is {}-bit".format(max_bits))
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print("maximum page span size is {} ({})".format(max_page_span, max_page_span * 4096))
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for size_class in size_classes:
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choices = []
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for bits in range(1, max_bits + 1):
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used = size_class * bits
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real = page_align(used)
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if real > 65536:
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continue
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pages = real / 4096
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efficiency = used / real * 100
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choices.append((bits, used, real, pages, efficiency))
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choices.sort(key=lambda x: x[4], reverse=True)
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print()
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print("size_class:", size_class)
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for choice in choices[:10]:
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print(choice)
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