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bloomfilter.py
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"""
This module provides the bloom filter support.
The Bloom filter, conceived by Burton Howard Bloom in 1970, is a space-efficient probabilistic data
structure that is used to test whether an element is a member of a set. False positives are
possible, but false negatives are not. Elements can be added to the set, but not removed (though
this can be addressed with a counting filter). The more elements that are added to the set, the
larger the probability of false positives.
Initial Bloomfilter implementation based on pybloom by Jay Baird <[email protected]> and Bob
Ippolito <[email protected]>. Simplified, and optimized to use just python code.
@author: Boudewijn Schoon
@organization: Technical University Delft
@contact: [email protected]
"""
from hashlib import sha1, sha256, sha384, sha512, md5
from math import ceil, log
from struct import Struct
from binascii import hexlify, unhexlify
from .decorator import Constructor, constructor
from .revision import update_revision_information
if __debug__:
from time import time
from .dprint import dprint
from .decorator import attach_profiler
# update version information directly from SVN
update_revision_information("$HeadURL$", "$Revision$")
class BloomFilter(Constructor):
def _init_(self, m_size, k_functions, prefix, filter_):
assert isinstance(m_size, int)
assert 0 < m_size
assert m_size % 8 == 0, "size must be a multiple of eight (%d)" % m_size
assert isinstance(k_functions, int)
assert 0 < k_functions <= m_size
assert isinstance(prefix, str)
assert 0 <= len(prefix) < 256
assert isinstance(filter_, long)
self._m_size = m_size
self._k_functions = k_functions
self._prefix = prefix
self._filter = filter_
if __debug__:
dprint("m size: ", m_size, " ~", m_size / 8, " bytes")
dprint("k functions: ", k_functions)
dprint("prefix: ", prefix.encode("HEX"))
dprint("filter: ", filter_)
hypothetical_error_rates = [0.4, 0.3, 0.2, 0.1, 0.01, 0.001, 0.0001]
dprint("hypothetical error rate: ", " | ".join("%.4f" % hypothetical_error_rate for hypothetical_error_rate in hypothetical_error_rates))
dprint("hypothetical capacity: ", " | ".join("%6d" % self.get_capacity(hypothetical_error_rate) for hypothetical_error_rate in hypothetical_error_rates))
# determine hash function
if m_size >= (1 << 31):
fmt_code, chunk_size = "Q", 8
elif m_size >= (1 << 15):
fmt_code, chunk_size = "L", 4
else:
fmt_code, chunk_size = "H", 2
# we need at most chunk_size * k bits from our hash function
bits_required = chunk_size * k_functions * 8
assert bits_required <= 512, "Combining multiple hashfunctions is not implemented, cannot create a hash for %d bits" % bits_required
if bits_required > 384:
hashfn = sha512
elif bits_required > 256:
hashfn = sha384
elif bits_required > 160:
hashfn = sha256
elif bits_required > 128:
hashfn = sha1
else:
hashfn = md5
self._fmt_unpack = Struct(">" + (fmt_code * k_functions) + ("x" * (hashfn().digest_size - bits_required / 8))).unpack
self._salt = hashfn(prefix)
@constructor(str, int)
def _init_bytes_k_(self, bytes_, k_functions, prefix=""):
assert isinstance(bytes_, str)
assert 0 < len(bytes_)
if __debug__: dprint("constructing bloom filter based on ", len(bytes_), " bytes and k_functions ", k_functions)
filter = long(hexlify(bytes_[::-1]), 16)
self._init_(len(bytes_) * 8, k_functions, prefix, filter)
@constructor(int, float)
def _init_m_f(self, m_size, f_error_rate, prefix=""):
assert isinstance(m_size, int)
assert 0 < m_size
assert m_size % 8 == 0, "size must be a multiple of eight (%d)" % m_size
assert isinstance(f_error_rate, float)
assert 0 < f_error_rate < 1
# calculate others
# self._n = int(m * ((log(2) ** 2) / abs(log(f))))
# self._k = int(ceil(log(2) * (m / self._n)))
if __debug__: dprint("constructing bloom filter based on m_size ", m_size, " bits and f_error_rate ", f_error_rate)
self._init_(m_size, self._get_k_functions(m_size, self._get_n_capacity(m_size, f_error_rate)), prefix, 0L)
@constructor(float, int)
def _init_n_f(self, f_error_rate, n_capacity, prefix=""):
assert isinstance(f_error_rate, float)
assert 0 < f_error_rate < 1
assert isinstance(n_capacity, int)
assert 0 < n_capacity
m_size = abs((n_capacity * log(f_error_rate)) / (log(2) ** 2))
m_size = int(ceil(m_size / 8.0) * 8)
if __debug__: dprint("constructing bloom filter based on f_error_rate ", f_error_rate, " and ", n_capacity, " capacity")
self._init_(m_size, self._get_k_functions(m_size, n_capacity), prefix, 0L)
def add(self, key):
"""
Add KEY to the BloomFilter.
"""
filter_ = self._filter
h = self._salt.copy()
h.update(key)
for pos in self._fmt_unpack(h.digest()):
filter_ |= 1 << (pos % self._m_size)
self._filter = filter_
def add_keys(self, keys):
"""
Add a sequence of KEYS to the BloomFilter.
"""
filter_ = self._filter
salt_copy = self._salt.copy
m_size = self._m_size
fmt_unpack = self._fmt_unpack
for key in keys:
assert isinstance(key, str)
h = salt_copy()
h.update(key)
# 04/05/12 Boudewijn: using a list instead of a generator is significantly faster.
# while generators are more memory efficient, this list will be relatively short.
# 07/05/12 Niels: using no list at all is even more efficient/faster
for pos in fmt_unpack(h.digest()):
filter_ |= 1 << (pos % m_size)
self._filter = filter_
def clear(self):
"""
Set all bits in the filter to zero.
"""
self._filter = 0L
def __contains__(self, key):
filter_ = self._filter
m_size_ = self._m_size
h = self._salt.copy()
h.update(key)
for pos in self._fmt_unpack(h.digest()):
if not filter_ & (1 << (pos % m_size_)):
return False
return True
def not_filter(self, iterator):
"""
Yields all tuples in iterator where the first element in the tuple is NOT in the bloom
filter.
"""
filter_ = self._filter
salt_copy = self._salt.copy
m_size = self._m_size
fmt_unpack = self._fmt_unpack
for tup in iterator:
assert isinstance(tup, tuple)
assert len(tup) > 0
assert isinstance(tup[0], str)
h = salt_copy()
h.update(tup[0])
# 04/05/12 Boudewijn: using a list instead of a generator is significantly faster.
# while generators are more memory efficient, this list will be relatively short.
# 07/05/12 Niels: using no list at all is even more efficient/faster
for pos in fmt_unpack(h.digest()):
if not filter_ & (1 << (pos % m_size)):
yield tup
break
def _get_k_functions(self, m_size, n_capacity):
return int(ceil(log(2) * m_size / n_capacity))
def _get_n_capacity(self, m_size, f_error_rate):
return int(m_size * (log(2) ** 2 / abs(log(f_error_rate))))
def get_capacity(self, f_error_rate):
"""
Returns the capacity given a certain error rate.
@rtype: int
"""
assert isinstance(f_error_rate, float)
assert 0 < f_error_rate < 1
return self._get_n_capacity(self._m_size, f_error_rate)
def get_bits_checked(self):
return sum(1 if self._filter & (1 << i) else 0 for i in range(self._m_size))
@property
def size(self):
"""
The size of the bloom filter in bits (m).
@rtype: int
"""
return self._m_size
@property
def functions(self):
"""
The number of functions used for each item (k).
"""
return self._k_functions
@property
def prefix(self):
"""
The prefix.
@rtype: string
"""
return self._prefix
@property
def bytes(self):
#hex should be m_size/4, hex is 16 instead of 8 -> hence half the number of "hexes" in m_size
hex = '%x' % self._filter
padding = '0'*(self._m_size/4 - len(hex))
return unhexlify(padding + hex)[::-1]
if __debug__:
def _test_behavior():
length = 1024
f_error_rate = 0.15
m_size = length * 8
b = BloomFilter(m_size, f_error_rate)
assert len(b.bytes) == length, b.bytes
for i in xrange(1000):
b.add(str(i))
print b.size, b.get_capacity(f_error_rate), b.bytes.encode("HEX")
d = BloomFilter(b.bytes, b.functions)
assert b.size == d.size
assert b.functions == d.functions
assert b.bytes == d.bytes
for i in xrange(1000):
assert str(i) in d
print d.size, d.get_capacity(f_error_rate), d.bytes.encode("HEX")
def _performance_test():
def test2(bits, count, constructor = BloomFilter):
generate_begin = time()
ok = 0
data = [(i, sha1(str(i)).digest()) for i in xrange(count)]
create_begin = time()
bloom = constructor(0.0001, bits)
fill_begin = time()
for i, h in data:
if i % 2 == 0:
bloom.add(h)
check_begin = time()
for i, h in data:
if (h in bloom) == (i % 2 == 0):
ok += 1
write_begin = time()
string = str(bloom)
write_end = time()
print "generate: {generate:.1f}; create: {create:.1f}; fill: {fill:.1f}; check: {check:.1f}; write: {write:.1f}".format(generate=create_begin-generate_begin, create=fill_begin-create_begin, fill=check_begin-fill_begin, check=write_begin-check_begin, write=write_end-write_begin)
print string.encode("HEX")[:100], "{len} bytes; ({ok}/{total} ~{part:.0%})".format(len=len(string), ok=ok, total=count, part=1.0*ok/count)
def test(bits, count, constructor = BloomFilter):
ok = 0
create_begin = time()
bloom = constructor(0.0001, bits)
fill_begin = time()
for i in xrange(count):
if i % 2 == 0:
bloom.add(str(i))
check_begin = time()
for i in xrange(count):
if (str(i) in bloom) == (i % 2 == 0):
ok += 1
write_begin = time()
string = str(bloom)
write_end = time()
print "create: {create:.1f}; fill: {fill:.1f}; check: {check:.1f}; write: {write:.1f}".format(create=fill_begin-create_begin, fill=check_begin-fill_begin, check=write_begin-check_begin, write=write_end-write_begin)
print string.encode("HEX")[:100], "{len} bytes; ({ok}/{total} ~{part:.0%})".format(len=len(string), ok=ok, total=count, part=1.0*ok/count)
b = BloomFilter(100, 0.0001)
b.add("Hello")
data = str(b)
#c = BloomFilter(data, 0)
#assert "Hello" in c
#assert not "Bye" in c
test2(10, 10,FasterBloomFilter)
test2(10, 100,FasterBloomFilter)
test2(100, 100,FasterBloomFilter)
test2(100, 1000,FasterBloomFilter)
test2(1000, 1000,FasterBloomFilter)
test2(1000, 10000,FasterBloomFilter)
test2(10000, 10000,FasterBloomFilter)
test2(10000, 100000,FasterBloomFilter)
test(10, 10,FasterBloomFilter)
test(10, 100,FasterBloomFilter)
test(100, 100,FasterBloomFilter)
test(100, 1000,FasterBloomFilter)
test(1000, 1000,FasterBloomFilter)
test(1000, 10000,FasterBloomFilter)
test(10000, 10000,FasterBloomFilter)
test(10000, 100000,FasterBloomFilter)
test(100000, 100000,FasterBloomFilter)
test(100000, 1000000,FasterBloomFilter)
#test2(10, 10)
#test2(10, 100)
# generate: 0.0; create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000001d000000241400480001840684024080408012800008012424018008a0401001080280008500241000 45 bytes; (10/10 ~100%)
# generate: 0.0; create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000001d000000bfbedf7fbafff4bffff7fdb7efdffe8df74f9fff6dbffb7bed7fdaf9ae76dfefffebffdb03 45 bytes; (90/100 ~90%)
test2(100, 100)
test2(100, 1000)
# generate: 0.0; create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000002001000002050100400001820008020388084422108050c0b41440804a003044204020082804000049820c880420 368 bytes; (100/100 ~100%)
# generate: 0.0; create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a000000200100009eedefcc77df2fff1feffe5fdeeefebffefe7fddffb77bf1cff574ddbedffafdbffffdf6fdef7f9ebf7f 368 bytes; (919/1000 ~92%)
test2(1000, 1000)
test2(1000, 10000)
# generate: 0.0; create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000003c0b0000a203040502001140c0000010840900420a06152400042000004222010090000022861000824010102001 3603 bytes; (1000/1000 ~100%)
# generate: 0.0; create: 0.0; fill: 0.1; check: 0.1; write: 0.0
# 0a0000003c0b0000fad3ffeffffdfb7efb5efffcfefffceffb7fffb7df3ffff99f7bffd5fdd7f65d76e7ff2f9feffcda7fff 3603 bytes; (9279/10000 ~93%)
test2(10000, 10000)
test2(10000, 100000)
# generate: 0.0; create: 0.0; fill: 0.1; check: 0.1; write: 0.0
# 0a00000054700000205286262400208041034085040005524802d8667048204220001214805020502002600408060080d009 35953 bytes; (10000/10000 ~100%)
# generate: 0.2; create: 0.0; fill: 0.7; check: 1.3; write: 0.0
# 0a00000054700000fbfffffeffffffbbfffffff7edbfffffff7fdffff7dbffffffffffbf9efafffbfffff5dddbdfffffd7ff 35953 bytes; (92622/100000 ~93%)
#test(10, 10)
#test(10, 100)
# create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000001d00000081012001030240322100040400440c510024402060400100010410088c0005020a18020100 45 bytes; (10/10 ~100%)
# create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000001d000000ebfff7fbefdedfbbeffffdeee7ddbf7fb7fdff77ffff77f5d74dff9efdffffffef7f9e3f03 45 bytes; (92/100 ~92%)
test(100, 100)
test(100, 1000)
# create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000002001000000108007008010210218120a0802824800806a20911008424200a00a0000114000100009466002820916 368 bytes; (100/100 ~100%)
# create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a000000200100007ff7f777fabadfffd7fddfdf29dfdefe77fc7bedfffc7df37e7ff9ffbbfff57fb7feffcfdffd7ffffdbf 368 bytes; (915/1000 ~92%)
test(1000, 1000)
test(1000, 10000)
# create: 0.0; fill: 0.0; check: 0.0; write: 0.0
# 0a0000003c0b00000146869100238482200450100090040002000010000006244000000c4a0141040402210802000c208010 3603 bytes; (1000/1000 ~100%)
# create: 0.0; fill: 0.1; check: 0.1; write: 0.0
# 0a0000003c0b0000f7ffffbbdbfbefffeffff7ff5cffff27f6defffadff76ef5fbfbecffdfd7fdee77f7ffdffea07dfebbdf 3603 bytes; (9279/10000 ~93%)
test(10000, 10000)
test(10000, 100000)
# create: 0.0; fill: 0.1; check: 0.1; write: 0.0
# 0a00000054700000130050403102c002410c410200a100700200cc0c0007620100142c408c4a82080082000a866d1818a211 35953 bytes; (10000/10000 ~100%)
# create: 0.0; fill: 0.8; check: 1.4; write: 0.0
# 0a000000547000009ffefff7fdffecff7dffffbeeefffffefffdffeef9efffffebff7ffdffffbfffd7ffeeefff7ffdfbffff 35953 bytes; (92520/100000 ~93%)
test(100000, 100000)
test(100000, 1000000)
def _taste_test():
def pri(f, m, invert=False):
set_bits = 0
for c in f._bytes.tostring():
s = "{0:08d}".format(int(bin(ord(c))[2:]))
for bit in s:
if invert:
if bit == "0":
bit = "1"
else:
bit = "0"
if bit == "1":
set_bits += 1
print s,
percent = 100 * set_bits / f.bits
print "= {0:2d} bits or {1:2d}%:".format(set_bits, percent), m
def gen(l, m):
if len(l) <= 10:
for e in l:
f = BloomFilter(NUM_SLICES, BITS_PER_SLICE)
f.add(e)
pri(f, e)
f = BloomFilter(NUM_SLICES, BITS_PER_SLICE)
map(f.add, l)
if len(l) <= 10:
pri(f, m + ": " + ", ".join(l))
else:
pri(f, m + ": " + l[0] + "..." + l[-1])
return f
NUM_SLICES, BITS_PER_SLICE = 1, 25
# a = gen(["kittens", "puppies"], "User A")
# b = gen(["beer", "bars"], "User B")
# c = gen(["puppies", "beer"], "User C")
# a = gen(map(str, xrange(0, 150)), "User A")
# b = gen(map(str, xrange(100, 250)), "User B")
# c = gen(map(str, xrange(200, 350)), "User C")
a = gen(map(str, xrange(0, 10)), "User A")
b = gen(map(str, xrange(5, 15)), "User B")
c = gen(map(str, xrange(10, 20)), "User C")
if True:
print
pri(a&b, "A AND B --> 50%")
pri(a&c, "A AND C --> 0%")
pri(b&c, "B AND C --> 50%")
if True:
print
pri(a^b, "A XOR B --> 50%", invert=True)
pri(a^c, "A XOR C --> 0%", invert=True)
pri(b^c, "B XOR C --> 50%", invert=True)
def _test_documentation():
alice = ["cake", "lemonade", "kittens", "puppies"]
for x in alice:
b = BloomFilter(1, 32)
b.add(x)
dprint(x)
dprint(b._bytes.tostring(), binary=1)
bob = ["cake", "lemonade", "beer", "pubs"]
carol = ["beer", "booze", "women", "pubs"]
for x in carol:
b = BloomFilter(1, 32)
b.add(x)
dprint(x)
dprint(b._bytes.tostring(), binary=1)
a = BloomFilter(1, 32)
map(a.add, alice)
dprint(alice)
dprint(a._bytes.tostring(), binary=1)
b = BloomFilter(1, 32)
map(b.add, bob)
dprint(bob)
dprint(b._bytes.tostring(), binary=1)
c = BloomFilter(1, 32)
map(c.add, carol)
dprint(carol)
dprint(c._bytes.tostring(), binary=1)
dprint("Alice bic Bob: ", a.bic_occurrence(b))
dprint("Alice bic Carol: ", a.bic_occurrence(c))
dprint("Bob bic Carol: ", b.bic_occurrence(c))
# b2 = BloomFilter(10, 0.8)
# map(b2.add, t2)
# dprint(t1)
# dprint(str(b1), binary=1)
# dprint(t2)
# dprint(str(b2), binary=1)
def _test_occurrence():
a = BloomFilter(1, 16)
b = BloomFilter(1, 16)
assert a.and_occurrence(b) == 0
assert a.xor_occurrence(b) == 0
assert a.and_occurrence(a) == 0
assert a.xor_occurrence(a) == 0
assert b.and_occurrence(a) == 0
assert b.xor_occurrence(a) == 0
assert b.and_occurrence(b) == 0
assert b.xor_occurrence(b) == 0
a.add("a1")
a.add("a2")
a.add("a3")
b.add("b1")
b.add("b2")
dprint(a._bytes.tostring(), binary=1)
dprint(b._bytes.tostring(), binary=1)
assert a.and_occurrence(b) == 1
assert a.xor_occurrence(b) == 3
def _test_save_load():
a = BloomFilter(1000, 0.1)
data = ["%i" % i for i in xrange(1000)]
map(a.add, data)
print a._num_slices, a._bits_per_slice
binary = str(a)
open("bloomfilter-out.data", "w+").write(binary)
print "Write binary:", len(binary)
try:
binary = open("bloomfilter-in.data", "r").read()
except IOError:
print "Input file unavailable"
else:
print "Read binary:", len(binary)
b = BloomFilter(binary, 0)
print b._num_slices, b._bits_per_slice
for d in data:
assert d in b
for d in ["%i" % i for i in xrange(10000, 1100)]:
assert not d in b
# def _test_false_positives(constructor = BloomFilter):
# for error_rate in [0.0001, 0.001, 0.01, 0.1, 0.4]:
# a = constructor(error_rate, 1024*8)
# p(a)
# data = ["%i" % i for i in xrange(int(a.capacity))]
# map(a.add, data)
# errors = 0
# for i in xrange(100000):
# if "X%i" % i in a:
# errors += 1
# print "Errors:", errors, "/", i + 1, " ~ ", errors / (i + 1.0)
# print
def _test_false_positives(constructor = BloomFilter):
for error_rate in [0.001, 0.01, 0.1, 0.5]:
begin = time()
# if constructor == BloomFilter:
# a = constructor(error_rate, 1024*8)
# capacity = a.capacity
# else:
a = constructor(1024*8, error_rate)
capacity = a.get_capacity(error_rate)
print "capacity:", capacity, " error-rate:", error_rate, "bits:", a.size, "bytes:", a.size / 8
data = ["%i" % i for i in xrange(capacity)]
map(a.add, data)
errors = 0
for i in xrange(200000):
if "X%i" % i in a:
errors += 1
end = time()
print "%.3f"%(end-begin), "Errors:", errors, "/", i + 1, " ~ ", errors / (i + 1.0)
print
def _test_prefix_false_positives(constructor = BloomFilter):
for error_rate in [0.0001, 0.001, 0.01, 0.1, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9]:
a = constructor(error_rate, 10374, prefix="A")
b = constructor(error_rate, 10374, prefix="B")
c = constructor(error_rate, 10374, prefix="C")
d = constructor(error_rate, 10374, prefix="D")
p(a)
print "Estimated errors:", a.error_rate, "->", a.error_rate * b.error_rate, "->", a.error_rate * b.error_rate * c.error_rate, "->", a.error_rate * b.error_rate * c.error_rate * d.error_rate
#we fill each bloomfilter up to its capacity
data = ["%i" % i for i in xrange(a.capacity)]
map(a.add, data)
map(b.add, data)
map(c.add, data)
map(d.add, data)
errors = 0
two_errors = 0
three_errors = 0
four_errors = 0
#we check what happens if we check twice the capacity
for i in xrange(a.capacity * 2):
if "X%i" % i in a:
errors += 1
if "X%i" % i in b:
two_errors += 1
if "X%i" % i in c:
three_errors += 1
if "X%i" % i in d:
four_errors += 1
print "Errors:", errors, "~", errors / (i + 1.0), "Two-Errors:", two_errors, "~", two_errors / (i + 1.0), "Three-Errors:", three_errors, "~", three_errors / (i + 1.0), four_errors, "~", four_errors / (i + 1.0)
print
def _test_performance():
from time import clock
from struct import pack
from random import random
from .database import Database
class TestDatabase(Database):
def check_database(self, *args):
pass
db = TestDatabase.get_instance(u"test.db")
DATA_COUNT = 1000
RUN_COUNT = 1000
db.execute(u"CREATE TABLE data10 (id INTEGER PRIMARY KEY AUTOINCREMENT, public_key TEXT, global_time INTEGER)")
db.execute(u"CREATE TABLE data500 (id INTEGER PRIMARY KEY AUTOINCREMENT, packet TEXT)")
db.execute(u"CREATE TABLE data1500 (id INTEGER PRIMARY KEY AUTOINCREMENT, packet TEXT)")
db.executemany(u"INSERT INTO data10 (public_key, global_time) VALUES (?, ?)", ((buffer("".join(chr(int(random() * 256)) for _ in xrange(83))), int(random() * 2**32)) for _ in xrange(DATA_COUNT)))
db.executemany(u"INSERT INTO data500 (packet) VALUES (?)", ((buffer("".join(chr(int(random() * 256)) for _ in xrange(500))),) for _ in xrange(DATA_COUNT)))
db.executemany(u"INSERT INTO data1500 (packet) VALUES (?)", ((buffer("".join(chr(int(random() * 256)) for _ in xrange(1500))),) for _ in xrange(DATA_COUNT)))
b10 = BloomFilter(1000, 0.1)
for public_key, global_time in db.execute(u"SELECT public_key, global_time FROM data10"):
b10.add(str(public_key) + pack("!Q", global_time))
b500 = BloomFilter(1000, 0.1)
for packet, in db.execute(u"SELECT packet FROM data500"):
b500.add(str(packet))
b1500 = BloomFilter(1000, 0.1)
for packet, in db.execute(u"SELECT packet FROM data1500"):
b1500.add(str(packet))
check10 = []
check500 = []
check1500 = []
for _ in xrange(RUN_COUNT):
start = clock()
for public_key, global_time in db.execute(u"SELECT public_key, global_time FROM data10"):
if not str(public_key) + pack("!Q", global_time) in b10:
raise RuntimeError("err")
end = clock()
check10.append(end - start)
start = clock()
for packet, in db.execute(u"SELECT packet FROM data500"):
if not str(packet) in b500:
raise RuntimeError("err")
end = clock()
check500.append(end - start)
start = clock()
for packet, in db.execute(u"SELECT packet FROM data1500"):
if not str(packet) in b1500:
raise RuntimeError("err")
end = clock()
check1500.append(end - start)
print DATA_COUNT, "*", RUN_COUNT, "=", DATA_COUNT * RUN_COUNT
print "check"
print "10 ", sum(check10)
print "500 ", sum(check500)
print "1500", sum(check1500)
def _test_size():
# 01/11/11 currently bloom filters get 10240 bits of space
b = BloomFilter(10240, 0.01)
b = BloomFilter(128*2, 0.01)
@attach_profiler
def _test_performance():
b = BloomFilter(1024 * 8, 0.01)
data = [str(i) for i in xrange(b.get_capacity(0.01))]
testdata = [str(i) for i in xrange(len(data) * 2)]
b.add_keys(data)
#for i in testdata:
# test = i in b
import sys
t1 = time()
for i in range(1000):
b.bytes
t2 = time()
bytes = b.bytes
for i in range(1000):
b2 = BloomFilter(bytes, b.functions)
print >> sys.stderr, time() - t2, t2 - t1
def p(b, postfix=""):
# print "capacity:", b.capacity, "error-rate:", b.error_rate, "num-slices:", b.num_slices, "bits-per-slice:", b.bits_per_slice, "bits:", b.size, "bytes:", b.size / 8, "packet-bytes:", b.size / 8 + 51 + 60 + 16 + 8, postfix
print "error-rate", b.error_rate, "bits:", b.size, "bytes:", b.size / 8, "packet-bytes:", b.size / 8 + 51 + 60 + 16 + 8, postfix
if __name__ == "__main__":
# _test_behavior()
# _performance_test()
# _taste_test()
# _test_occurrence()
# _test_documentation()
# _test_save_load()
# _test_performance()
# _test_false_positives()
# _test_prefix_false_positives()
# _test_prefix_false_positives(FasterBloomFilter)
# _test_behavior(FasterBloomFilter)
# _test_size()
_test_performance()
# MTU = 1500 # typical MTU
# # MTU = 576 # ADSL
# DISP = 51 + 60 + 16 + 8
# BITS = 9583 # currently used bloom filter size
# # BITS = (MTU - 20 - 8 - DISP) * 8 # size allowed by MTU (typical header)
# BITS = (MTU - 60 - 8 - DISP) * 8 # size allowed by MTU (max header)
# # b1 = BloomFilter(1000, 0.01)
# # p(b1)
# # b2 = BloomFilter(0.01, b1.size)
# # p(b2)
# b3 = BloomFilter(0.001, BITS)
# p(b3)
# b3 = BloomFilter(0.01, BITS)
# p(b3)
# b3 = BloomFilter(0.1, BITS)
# p(b3)
# b4 = BloomFilter(0.5, BITS)
# p(b4)