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First batch of bug fixes to simulator

This commit is contained in:
vub 2017-02-24 03:22:51 -05:00
parent e9c69f679d
commit dd3f3b8b7d
1 changed files with 46 additions and 30 deletions
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76
casper4/simulator.py
View File

@ -4,11 +4,11 @@ import random
NODE_COUNT = 20
BLOCK_TIME = 100
EPOCH_LENGTH = 100
AVG_LATENCY = 30
EPOCH_LENGTH = 25
AVG_LATENCY = 50
def poisson_latency(latency):
return lambda: int(random.gammavariate(1, 1) * latency)
return lambda: 1 + int(random.gammavariate(1, 1) * latency)
class Network():
def __init__(self, latency):
@ -18,9 +18,9 @@ class Network():
self.msg_arrivals = {}
def broadcast(self, msg):
delay = self.latency()
for i, n in enumerate(self.nodes):
if self.time + delay not in self.msg_arrivals[i]:
delay = self.latency()
if self.time + delay not in self.msg_arrivals:
self.msg_arrivals[self.time + delay] = []
self.msg_arrivals[self.time + delay].append((i, msg))
@ -28,7 +28,7 @@ class Network():
if self.time in self.msg_arrivals:
for node_index, msg in self.msg_arrivals[self.time]:
self.nodes[node_index].on_receive(msg)
del self.msg_arrivals[self.time]
del self.msg_arrivals[self.time]
for n in self.nodes:
n.tick(self.time)
self.time += 1
@ -69,7 +69,7 @@ GENESIS = Block()
class Node():
def __init__(self, network, id):
# List of highest-commit descendants along with their commit counts, in oldest-to-newest order
self.checkpoints = [GENESIS]
self.checkpoints = [GENESIS.hash]
# Received blocks
self.received = {GENESIS.hash: GENESIS}
# Messages that will be processed once a given message is received
@ -85,17 +85,23 @@ class Node():
self.current_epoch = 0
# My highest committed epoch and hash
self.highest_committed_epoch = -1
self.highest_committed_hash = None
self.highest_committed_hash = GENESIS.hash
# Network I am connected to
self.network = network
network.nodes.append(self)
# Longest tail from each checkpoint
self.tails = {}
self.tails = {GENESIS.hash: GENESIS}
# Tail that each block belongs to
self.tail_membership = {}
self.tail_membership = {GENESIS.hash: GENESIS.hash}
# This node's ID
self.id = id
@property
def head(self):
latest_checkpoint = self.checkpoints[-1]
latest_block = self.tails[latest_checkpoint]
return latest_block
# Get the checkpoint immediately before a given checkpoint
def get_checkpoint_parent(self, block):
if block.number == 0:
@ -129,7 +135,7 @@ class Node():
# If we didn't receive the block's parent yet, wait
if block.prevhash not in self.received:
self.add_dependency(block.prevhash, block)
return
return False
# We recived the block
self.received[block.hash] = block
# If the block is an epoch block of a higher epoch
@ -148,9 +154,12 @@ class Node():
# Otherwise...
else:
# See if it's part of the longest tail, if so set the tail accordingly
assert block.prevhash in self.received
assert block.prevhash in self.tail_membership
self.tail_membership[block.hash] = self.tail_membership[block.prevhash]
if block.number > self.tails[self.tail_membership[block.hash]].number:
self.tails[self.tail_membership[block.hash]] = block
return True
# Pick a checkpoint by number of commits first, epoch number
# (ie. longest chain rule) second
@ -201,7 +210,7 @@ class Node():
# If the block has not yet been received, wait
if prepare.hash not in self.received:
self.add_dependency(prepare.hash, prepare)
return
return False
# Add to the prepare count
if prepare.hash not in self.prepare_count:
self.prepare_count[prepare.hash] = {}
@ -225,45 +234,52 @@ class Node():
self.highest_committed_epoch = prepare.view
self.highest_committed_hash = prepare.hash
self.current_epoch = prepare.view + 1
return True
# Called on receiving a commit message
def accept_commit(self, commit):
# If the block has not yet been received, wait
if commit.hash not in self.received:
self.add_dependency(commit.hash, commit)
return
return False
# If there have not yet been enough prepares, wait
if commit.hash not in self.committable:
self.add_dependency("commit:"+str(commit.hash), commit)
return
return False
# Add commits, and update checkpoints if needed
self.commits[commit.hash] += 1
if self.commits[commit.hash] % 10 == 0:
self.check_checkpoints(self.received[commit.hash])
return True
# Called on receiving any object
def on_receive(self, obj):
if obj.hash in self.received:
return False
if isinstance(obj, Block):
self.accept_block(obj)
o = self.accept_block(obj)
elif isinstance(obj, Prepare):
self.accept_prepare(obj)
o = self.accept_prepare(obj)
elif isinstance(obj, Commit):
self.accept_commit(obj)
self.received[obj.hash] = obj
if obj.hash in self.dependencies:
for d in self.dependencies[obj.hash]:
self.on_receive(d)
del self.dependencies[obj.hash]
o = self.accept_commit(obj)
# If the object was successfully processed
# (ie. not flagged as having unsatisfied dependencies)
if o:
self.received[obj.hash] = obj
if obj.hash in self.dependencies:
for d in self.dependencies[obj.hash]:
self.on_receive(d)
del self.dependencies[obj.hash]
# Called every round
def tick(self):
if self.id == (self.time // BLOCK_TIME) % NODE_COUNT and self.time % BLOCK_TIME == 0:
latest_checkpoint = self.checkpoints[-1]
latest_block = self.tails[latest_checkpoint]
new_block = Block(latest_block)
def tick(self, _time):
if self.id == (_time // BLOCK_TIME) % NODE_COUNT and _time % BLOCK_TIME == 0:
new_block = Block(self.head)
self.network.broadcast(new_block)
n = Network(poisson_latency(AVG_LATENCY))
nodes = [Node(n, i) for i in range(NODE_COUNT)]
network = Network(poisson_latency(AVG_LATENCY))
nodes = [Node(network, i) for i in range(NODE_COUNT)]
for t in range(10000):
n.tick()
network.tick()
if t % 100 == 0:
print([n.head.number for n in nodes])