add token_emission.py

quarkchain/experimental/token_emission.py

@@ -0,0 +1,74 @@
+# Parameters
+GENESIS_TIMESTAMP = 1556639999
+GENESIS_SUPPLY = 6 * (10 ** 9) * (10 ** 18) # 6B
+
+ROOT_BLOCK_TIME = 60  # actual ~ 57.79
+ROOT_EPOCH_INTERVAL = 525600
+ROOT_BLOCK_REWARD = 156000000000000000000
+
+SHARD_BLOCK_TIME = 10  # actual ~ 9.76
+SHARD_EPOCH_INTERVAL = 3153600
+SHARD_GENESIS_NUMBER = 8
+SHARD_BLOCK_REWARD = 6500000000000000000
+
+
+def get_chain_reward(bn, epoch_interval, block_reward):
+    r = 0
+    while bn != 0:
+        b = min(bn, epoch_interval)
+        bn -= b
+        r += block_reward * b
+        block_reward = block_reward * 88 // 100
+    return r
+
+
+def get_circulating_supply_by_bn(bns):
+    cs = GENESIS_SUPPLY + get_chain_reward(bns[0], ROOT_EPOCH_INTERVAL, ROOT_BLOCK_REWARD)
+    for i in range(1, 9):
+        cs += get_chain_reward(bns[i], SHARD_EPOCH_INTERVAL, SHARD_BLOCK_REWARD)
+    sbreward = SHARD_BLOCK_REWARD
+    for i in range(9, len(bns)):
+        sbreward = sbreward * 88 // 100
+        cs += get_chain_reward(bns[i], SHARD_EPOCH_INTERVAL, sbreward) * 3 // 2 # 1 new shardds, and 0.5 will be root chains
+    return cs
+
+
+def get_circulating_supply(ts, with_new_shards=False):
+    if ts < GENESIS_TIMESTAMP:
+        return 0
+
+    bns = [(ts - GENESIS_TIMESTAMP) // ROOT_BLOCK_TIME]
+    bns += [(ts - GENESIS_TIMESTAMP) // SHARD_BLOCK_TIME] * 8
+    if with_new_shards:
+        # May add one shard per year, which will have the same emission as existin shard at the time of creation.
+        # This means the genesis reward for the shard is already reduced.
+        sbreward = SHARD_BLOCK_REWARD
+        for i in range((ts - GENESIS_TIMESTAMP) // SHARD_BLOCK_TIME // SHARD_EPOCH_INTERVAL):
+            bns.append((ts - GENESIS_TIMESTAMP) // SHARD_BLOCK_TIME - SHARD_EPOCH_INTERVAL * (i + 1))
+    return get_circulating_supply_by_bn(bns)
+
+
+def print_end_of_month_supply():
+    import calendar
+    import datetime
+
+    dt = datetime.datetime(2021, 12, 31, 0, 0)
+    print("{}: {}".format(dt, get_circulating_supply(int(dt.timestamp()), with_new_shards=True) / 1e18))
+
+    for year in range(2022, 2025):
+        for month in range(1, 13):
+            day = calendar.monthrange(year, month)[1]
+            dt = datetime.datetime(year, month, day, 0, 0)
+            print("{}: {}".format(dt, get_circulating_supply(int(dt.timestamp()), with_new_shards=True) / 1e18))
+
+
+print(get_circulating_supply_by_bn([222898, 1285646, 1278508, 1279479, 1277021, 1282227, 1278981, 1275374, 1277279]) / 1e18) # 6101296435.5
+print(get_circulating_supply_by_bn([1294545, 7600468, 7555507, 7562667, 7588454, 7595046, 7552602, 7584632, 7464263]) / 1e18) # 6542409279.3184
+print(get_circulating_supply_by_bn([1419566, 8375518, 8340637, 8352809, 8412933, 8388349, 8330705, 8348813, 8230480]) / 1e18) # 6589106535.1807995
+
+print(get_circulating_supply(1638686770) / 1e18) # 6577057566.592
+print(get_circulating_supply(1638686770, with_new_shards=True) / 1e18) # 6632768875.2736
+print(get_circulating_supply(40000000000, with_new_shards=False) / 1e18) # 8049840000.0 (max cap without new shards)
+print(get_circulating_supply(40000000000, with_new_shards=True) / 1e18) # 9928860000.0 (max cap)
+
+print_end_of_month_supply()