/
gpdb.py
55 lines (43 loc) · 1.23 KB
/
gpdb.py
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from random import shuffle, choice
class Node:
__slots__ = ('has_knowledge', 'peers')
def __init__(self):
self.has_knowledge = False
self.peers = None
def tell(self):
if self.has_knowledge and self.peers:
peer = choice(list(self.peers))
peer.recv(self)
self.peers.remove(peer)
return peer, True
return None, False
def recv(self, sender):
self.peers.remove(sender)
self.has_knowledge = True
def allocate(size):
peers = set(Node() for _ in range(size))
for node in peers:
node.peers = peers - {node}
start = next(iter(peers))
start.has_knowledge = True
return start
def simulate(size, bandwidth, messages):
start = allocate(size)
knows = {start}
while True:
quota = bandwidth
T = {node: messages for node in knows}
while T and quota > 0:
node, count = T.popitem()
if count == 0:
continue
peer, ok = node.tell()
if not ok:
continue
knows.add(peer)
T[node] = count - 1
quota -= 1
k = len(knows)
yield k
if k == size:
break