def creat_finger_table(self):
print("creat_finger_table...")
bar = ProgressBar(total=self.total)
# finger list is like [1, 2, 4, 8...]
finger = list()
i = 1
while i < self.SIZE/2 + 1:
finger.append(i)
i *= 2
for _, now in self.chord.items():
for i in finger:
target = (i + now.address) % self.SIZE
finded_flag = False
first_address = None
for _, node in self.chord.items():
if first_address is None:
first_address = node.address
if node.address >= target and node.address is not now.address:
now.finger_table[i] = node.address
finded_flag = True
break
if not finded_flag:
now.finger_table[i] = first_address
bar.next()
def __init__(self, int_nodeList, ID_SIZE):
print("init chord...")
bar = ProgressBar(total=len(int_nodeList))
self.node_list = sorted(int_nodeList)
# create Node object
self.chord = OrderedDict()
for num in self.node_list:
self.chord[num] = Node(num, self)
bar.next()
print("done.")
self.total = len(self.chord)
# size of chord
self.SIZE = ID_SIZE
self.set_neighbor()
self.creat_finger_table()
def set_neighbor(self):
print("set neighbor...")
bar = ProgressBar(total=self.total)
first = None
previous = None
for _, now in self.chord.items():
# save first node address
if first == None:
first = now
elif previous != None:
# set the previous of now Node
now.predecessor = previous
# set the next of previous Node
previous.successor = now
previous = now
bar.next()
# next of last node is first node
previous.successor = first
# pre of first node is last node
first.predecessor = previous
print("done.")
def main():
# if file not exist, create it.
nodes = myRandom.random_file(RANDOM_FILE, ID_SIZE, NODE_NUMBER)
# assume we already have all nodes at first time
chord = _chord.Chord(nodes, ID_SIZE)
#################################
# Q1: 每一個節點所需負責之key值個數 #
#################################
print("\n===========Q1=============")
count = dict()
# no matter what node start, get same answer
node_index = nodes[randint(0, NODE_NUMBER - 1)]
node = chord.chord[node_index]
print("start node:", node)
for i in range(1, 11):
file_count = i * 10 * NODE_NUMBER
print("numK:", file_count)
bar = ProgressBar(total=file_count)
# clear count
for j in nodes:
count[j] = 0
for _ in range(file_count):
file_key = randint(0, ID_SIZE - 1)
addr, record = node.search(file_key, list())
logs.debug(node, "find", file_key, ">> ")
logs.debug("\tnode:", addr, " record:", record)
# use random list `nodes` mapping
count[addr] += 1
bar.next()
# cacalculate ans
ans = sorted(count.items(), key=operator.itemgetter(1))
max = ans[0][1]
mid = ans[NODE_NUMBER // 2][1]
min = ans[NODE_NUMBER - 1][1]
print(max, mid, min)
#######################
# Q2: 搜尋時所需之hop數 #
#######################
print("\n===========Q2=============")
hops = [0] * int(log(ID_SIZE, 2))
bar = ProgressBar(total=100 * NODE_NUMBER)
for i in nodes:
node = chord.chord[i]
for j in range(100):
k = randint(0, ID_SIZE - 1)
addr, record = node.search(k, [])
hops_num = len(record) - 1
hops[hops_num] += 1
bar.next()
print("total hops:\n", hops)
print("proportion of total hops:\n",
[x / (100 * NODE_NUMBER) for x in hops])
