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hardened_malloc
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calculate internal fragmentation for size classes

pull/50/head
Daniel Micay 2018-08-23 17:29:42 -04:00
parent 4aa0fab4f4
commit 5bdf94da4a
1 changed files with 12 additions and 0 deletions
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12
calculate_waste.py
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@ -11,12 +11,24 @@ size_classes = [
10240, 12288, 14336, 16384 10240, 12288, 14336, 16384
] ]
print("size class", "worst case internal fragmentation", sep=", ")
print(16, "100%", sep=", ")
for i in range(len(size_classes) - 1):
size_class = size_classes[i + 1]
worst_case = size_classes[i] + 1
used = worst_case / size_class
print(size_class, str(100 - used * 100) + "%", sep=", ")
def page_align(size): def page_align(size):
return (size + 4095) & ~4095 return (size + 4095) & ~4095
max_bits = 256 max_bits = 256
max_page_span = 16 max_page_span = 16
print()
print("maximum bitmap size is {}-bit".format(max_bits)) print("maximum bitmap size is {}-bit".format(max_bits))
print("maximum page span size is {} ({})".format(max_page_span, max_page_span * 4096)) print("maximum page span size is {} ({})".format(max_page_span, max_page_span * 4096))