# Time between successful PoW solutions POW_SOLUTION_TIME = 10 # Time for a block to traverse the network TRANSIT_TIME = 50 # Number of required uncles UNCLES = 4 # Uncle block reward (normal block reward = 1) UNCLE_REWARD_COEFF = 0.875 # Reward for including uncles NEPHEW_REWARD_COEFF = 0.01 # Rounds to test ROUNDS = 80000 import random import copy class Miner(): def __init__(self, p): self.hashpower = p self.id = random.randrange(10000000) # Set up a few genesis blocks (since the algo is grandpa-dependent, # we need two genesis blocks plus some genesis uncles) self.blocks = { 0: {"parent": -1, "uncles": [], "miner": -1, "height": 0, "score": 0, "id": 0, "children": {1: 1}}, 1: {"parent": 0, "uncles": [], "miner": -1, "height": 1, "score": 0, "id": 1, "children": {}} } # ID of "latest block" self.head = 1 # Hear about a block def recv(self, block): # Add the block to the set if it's valid addme = True if block["id"] in self.blocks: addme = False if block["parent"] not in self.blocks: addme = False for u in block["uncles"]: if u not in self.blocks: addme = False p = self.blocks[block["parent"]] if addme: self.blocks[block["id"]] = copy.deepcopy(block) # Each parent keeps track of its children, to help # facilitate the rule that a block must have N+ siblings # to be valid if block["id"] not in p["children"]: p["children"][block["id"]] = block["id"] # Check if the new block deserves to be the new head if len(p["children"]) >= 1 + UNCLES: for c in p["children"]: newblock = self.blocks[c] if newblock["score"] > self.blocks[self.head]["score"]: self.head = newblock["id"] # Mine a block def mine(self): h = self.blocks[self.blocks[self.head]["parent"]] b = sorted(list(h["children"]), key=lambda x: -self.blocks[x]["score"]) p = self.blocks[b[0]] block = {"parent": b[0], "uncles": b[1:], "miner": self.id, "height": h["height"] + 2, "score": p["score"] + len(b), "id": random.randrange(1000000000000), "children": {}} self.recv(block) return block def cousin_degree(miner, b1, b2): while miner.blocks[b1]["height"] > miner.blocks[b2]["height"]: b1 = miner.blocks[b1]["parent"] while miner.blocks[b2]["height"] > miner.blocks[b1]["height"]: b2 = miner.blocks[b2]["parent"] t = 0 while b1 != b2: b1 = miner.blocks[b1]["parent"] b2 = miner.blocks[b2]["parent"] t += 1 return t percentages = [1]*25 + [5, 5, 5, 5, 5, 10, 15, 25] miners = [] for p in percentages: miners.append(Miner(p)) miner_dict = {} for m in miners: miner_dict[m.id] = m listen_queue = [] for t in range(ROUNDS): if t % 5000 == 0: print t for m in miners: R = random.randrange(POW_SOLUTION_TIME * sum(percentages)) if R < m.hashpower and t < ROUNDS - TRANSIT_TIME * 3: b = m.mine() listen_queue.append([t + TRANSIT_TIME, b]) while len(listen_queue) and listen_queue[0][0] <= t: t, b = listen_queue.pop(0) for m in miners: m.recv(b) h = miners[0].blocks[miners[0].head] profit = {} total_blocks_in_chain = 0 length_of_chain = 0 ZORO = {} print "### PRINTING BLOCKCHAIN ###" while h["id"] > 1: print h["miner"], h["height"], h["score"] total_blocks_in_chain += 1 + len(h["uncles"]) ZORO[h["id"]] = True length_of_chain += 1 profit[h["miner"]] = profit.get(h["miner"], 0) + \ 1 + NEPHEW_REWARD_COEFF * len(h["uncles"]) for u in h["uncles"]: ZORO[u] = True u2 = miners[0].blocks[u] profit[u2["miner"]] = profit.get(u2["miner"], 0) + UNCLE_REWARD_COEFF h = miners[0].blocks[h["parent"]] print "### PRINTING HEADS ###" for m in miners: print m.head print "### PRINTING PROFITS ###" for p in profit: print miner_dict[p].hashpower, profit[p] print "### PRINTING RESULTS ###" groupings = {} counts = {} for p in profit: h = miner_dict[p].hashpower counts[h] = counts.get(h, 0) + 1 groupings[h] = groupings.get(h, 0) + profit[p] for c in counts: print c, groupings[c] / counts[c] / (groupings[1] / counts[1]) print " " print "Total blocks produced: ", len(miners[0].blocks) - 2 print "Total blocks in chain: ", total_blocks_in_chain print "Efficiency: ", total_blocks_in_chain * 1.0 / (len(miners[0].blocks) - 2) print "Average uncles: ", total_blocks_in_chain * 1.0 / length_of_chain print "Length of chain: ", length_of_chain print "Block time: ", ROUNDS * 1.0 / length_of_chain